The Ruff catches the small, early signs of pain that are easy to miss, long before your dog changes how it walks or acts in a way you would ever notice.
You've been invited
Founders Pack · The Ruff
Know before they show.
You are one of only 100 people ever invited to the Founders Pack. The Ruff reads your dog for the earliest signs of pain, explains what those signs mean in plain language, and tells you what to do about it, day and night.
Buy The Ruff
$249plus tax, calculated at checkout
Only 100 people have been invited to the Founders Pack.
What it does
It finds the pain, explains it, and tells you what to do.
The Ruff is not a health tracker and it is not a step counter. It does one thing, and it does it deeply.
Identify
Contextualize
It does not just flag a signal. It tells you what that signal likely means for your dog, measured against your dog's own normal rather than a textbook average.
Recommend
Then it tells you what to do next in plain language, so you are never left staring at a number wondering what it is trying to say.
Sensing
Six fused senses, working as one.
The Ruff reads your dog across six channels at once and fuses them into one read. Two IMUs for movement and gait, two microphones for the sounds your dog makes, a thermal sensor for body temperature, and 60GHz radar for the finest motion.
It arrives already knowing breed and size norms, then learns the rest of your individual dog from day one. Everything it flags is measured against your dog's own normal, so what matters is what changes.
Insight
A subtle change in hind-leg gait has shown up over the last 3 days.
Recommendation
Keep walks gentle this week and let us know if you notice any limping.
Why it matters
Because they can't tell you where it hurts.
Dogs mask pain by instinct. The Ruff reads the quiet signals they cannot say out loud, and shows you early.
The hardware
Every angle of The Ruff.
One sealed unit that mounts on your dog's collar. Matte, low profile, and built to disappear into your dog's day.
In the app
Everything your dog is telling you, in one place.
The Tether app · live view
This is the app you will open every day. The moment you tap in, you get a single Pain Probability Index for how your dog is doing right now, a live read from all 6 sensors, and what it means in plain language. Every pattern it surfaces comes with a clear next step, so you are never left staring at a number wondering what to do.
Pain Probability Index
How your dog is right now
A single, plain read of how your dog is doing at this moment, updated continuously.
Gait symmetry
How evenly they move
Side to side balance in how your dog carries itself, one of the earliest tells for discomfort.
Vocalization
What their sounds mean
What your dog's sounds are telling you, including the difference between fear, anxiety, and pain.
Recommendations
What to do next
Clear next steps written in plain language, so a reading always comes with an answer.
Scout
Answers from your dog's data
Ask anything about your dog and get a response grounded in your dog's own readings.
The Pulse
A quick check twice a week
A thirty second check-in that keeps the full picture current between everything else.
This build
About this founders build.
This founders build connects over WiFi at home and Bluetooth on the go. There is no cellular in this version.
When your dog is away from WiFi, out on a walk or a hike, The Ruff stays connected to your phone over Bluetooth and sends its alerts straight there. You get the full sensing experience across the day, at home and outside, without a cellular plan.
Getting started
On your dog in minutes.
No tools and no setup headaches. Four steps from the box to your dog's collar.
1
Charge it
Top it up over USB-C until the light shows a full charge.
2
Get the app
Download the Tether app on iPhone or Android and create your account.
3
Pair over Bluetooth
Hold The Ruff near your phone and the app connects to it in seconds.
4
Attach and go
Slide it onto your dog's flat collar, secure the keeper, and it starts learning.
Peace of mind
You will know they are okay.
No more second-guessing a limp or a quiet afternoon. The Ruff watches the things you cannot, so you can stop worrying and just be with your dog.
Specifications
The details.
IPX7
Water resistant
6
Fused senses
52×30×12mm
Device size
~15 days
Battery per charge
24/7
Continuous sensing
ConnectivityWiFi and BLE, no cellular
Sensing2 IMUs, 2 microphones, thermal sensor, 60GHz radar
Water resistanceIPX7, temporary immersion up to 3 feet
BatteryRechargeable, targeting ~15 days, USB-C
MountingFits most standard flat collars
AppiPhone and Android
In the boxThe Ruff, collar mount, USB-C cable, founders welcome box
Sensing windowContinuous, day and night
These figures describe the founders build. A few details, including exact size, finish, and battery life, may shift slightly as we finish production tooling. The honest details are just below.
A note from the co-founder
“We started Tether because of a dog I love. I watched him hide his pain until it was almost too late, and dogs are built to mask what hurts, so by the time we notice they have already been carrying it a long while. That was the spark, but building the answer was never something I did alone. My co-founder Alex Oberhauser and I made The Ruff into the tool I wished I had, something that listens closely enough to catch the quiet signs early and then tells you what to do next. You are one of the first hundred people to ever put it on a dog, and that means more to us than we can fit here.”
Rhett Rumery, Co-Founder and CEO
The pack
Your place in the Founders Pack.
You are one of only 100 people in the Founders Pack. Your place is a standing arrangement, not a one time purchase. Here is exactly what you get and what we ask for in return.
What your place includes
Every version of The Ruff, free
Your place covers this device and every future version we build, v2, v3, and onward, free for as long as you hold your place.
Your subscription, free
The full Tether experience, including Scout, stays free for you for as long as you hold your place. Everyone else pays monthly.
The founders package
Your device arrives with the founders welcome box, put together only for the people in this pack.
What we ask in return
Ten minutes a month
A short monthly read so we learn what is working and what is not, straight from you.
Two conversations a year
Two relaxed sit-downs with a small group of fellow members, about twenty minutes each.
Honest feedback
Tell us the truth about your dog, the device, and the app. That is the entire point of the pack.
Your benefits stay yours for as long as you take part. Keep up the monthly read and the two conversations a year and everything above continues. If you stop giving feedback, the free upgrades and the free subscription pause until you are back in.
Coverage
Backed for a year, shipped with care.
Warranty
One year limited warranty
Every Ruff is covered against manufacturing defects for one year from the day it arrives. If it fails through normal use, we will repair or replace it.
Shipping
Ships across the US and Canada
We expect your Ruff to ship in October 2026. Supply chain factors outside our control could shift that, and if they do, you will hear from us first. Tracking comes by email the moment it goes out.
Returns
Thirty day replacement
If something is not right with your unit, return it within 30 days of delivery and we will send you a new one. Founders Pack orders are not refundable, since your place already includes every future version and your subscription at no cost, and that trade only works when you are fully in.
Questions
Good to know.
What does The Ruff actually do?+
The Ruff watches for the earliest signs of pain in your dog, explains what those signs likely mean in plain language, and tells you what to do next. It is not a step counter or a wellness tracker. It is built to catch discomfort early, often before you would notice a change yourself.
How does it attach to my dog?+
The Ruff mounts onto most standard flat collars using its built in mount and keeper. It sits low and snug so your dog can wear it day and night, and you can move it between collars whenever you like.
What size dog is it for?+
We recommend The Ruff for dogs over 20 lbs, which covers most standard collar sizes. If your dog is smaller than that or you are not sure about the fit, contact us before you buy and we can give you a better answer for your dog.
Is it waterproof?+
The Ruff is rated IPX7, which means it handles rain, splashes, and temporary immersion in up to 3 feet of water. It is built for everyday wet and the occasional dunk, not for long submersion or swimming.
How long does the battery last?+
The Ruff is built to run around 15 days on a charge and recharges over USB-C. The app lets you know when it is time to top up.
Does it need cellular service?+
No. This build uses WiFi at home and Bluetooth when you are out, so there is no cellular plan and no monthly connectivity fee. Alerts reach your phone over Bluetooth when you are away from WiFi.
Does it work with my phone?+
Yes. The Tether app works on iPhone and Android, and it is where your Pain Probability Index, insights, and recommendations live.
Is The Ruff a medical device?+
No. The Ruff is an informational tool, not a medical or veterinary device. It does not diagnose illness and it does not replace your veterinarian. If you have a health concern about your dog, always talk to a licensed vet.
What does it listen to, and is my data private?+
The Ruff senses motion, gait, temperature, and sound patterns to understand how your dog is doing. Sound is processed to recognize patterns like vocalization, not to record and keep conversations. Your data powers your insights and helps improve the product. Full detail is in our privacy terms below.
When will it ship, and what is included?+
We expect your Ruff to ship in October 2026. That could move if we hit supply chain factors outside our control, and if it does, we will let you know first. In the box you get The Ruff, the collar mount, a USB-C cable, and the founders welcome box. Your founders benefits, every future version free and a free subscription, continue for as long as you take part.
The whole point
Catch it early. Give them more good days.
Every founders Ruff is one more dog whose pain gets caught before it turns into something bigger.
Straight with you
The honest details.
We would rather set clear expectations than overpromise. Here is exactly where things stand for the founders build, in plain terms, so there are no surprises later.
Early hardware
This is the first run
The design is locked, but small details like exact size, finish, and battery life may change slightly as we finish production tooling. Nothing about how The Ruff works will change.
Shipping timing
We expect October 2026
That is our honest target. Supply chain factors outside our control could move it. If the date changes, you will hear it from us first rather than from silence.
What it is
A tool, not a diagnosis
The Ruff helps you catch signs of pain early and points you in the right direction. It informs you, it does not diagnose, and it never replaces your veterinarian.
Early hardware always carries a few bugs, and we would rather be honest with ourselves than pretend otherwise. We do not expect many, but catching them early is a real part of why the Founders Pack exists. We would rather hear about them from you first, fix them quickly, and build the next version of The Ruff around what you find.
Checkout
Claim your founders unit.
$249
plus sales tax, calculated at checkout by where it ships
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Visa · Mastercard · American Express · Discover · Apple Pay · Google Pay
You pay $249 today. Sales tax is added at checkout based on where your Ruff ships. We expect to ship in October 2026, and we will let you know if that shifts. Every order is backed by a 1 year limited warranty and a 30 day replacement window. Founders Pack orders are not refundable.
The fine print
Terms, safety, and privacy.
Please read these before you buy. Using The Ruff means you agree to the terms below.
Health and safety, please read first
The Ruff is a consumer product that offers information about your dog. It is not a medical or veterinary device and it does not diagnose, treat, cure, or prevent any condition. Its insights can be incomplete or wrong and are not a substitute for professional veterinary care. Never delay seeking care from a licensed veterinarian because of anything The Ruff shows you, and never rely on it in an emergency. The Ruff is not a locator or safety device and should not be used to find or contain your dog. It contains small parts, so keep it away from dogs who chew, and check the fit and your dog's skin regularly. Stop use if you notice any irritation.
Terms of Service+
Agreement. These Terms of Service are a binding agreement between you and Vriend, Inc., doing business as Tether ("Tether", "we", "us"). By purchasing, activating, or using The Ruff or the Tether app, you agree to these terms. If you do not agree, do not buy or use the product. You must be at least 18 years old to purchase.
The Founders Pack. Your place in the Founders Pack is personal to you and may not be resold or transferred. Founders benefits, including future versions of The Ruff at no charge and a complimentary subscription, continue only for as long as you meet the feedback commitment described on this page. We may change, pause, or end the program or any benefit at any time and without prior notice, and early hardware and software may change over time.
License. The device firmware and the Tether app are licensed to you, not sold, for personal and non-commercial use with your own dog. You may not copy, modify, reverse engineer, or resell the software or the service.
Acceptable use. You agree to follow the setup and safety guidance, to use The Ruff only on a dog in your care, and not to use it for any unlawful purpose or in any way that could harm an animal or a person.
Changes. We may update these terms at any time and without prior notice. Continued use after an update means you accept the revised terms.
Health and safety disclaimer+
Not veterinary advice. The Ruff and the Tether app provide general information and are not veterinary advice, diagnosis, or treatment. Outputs such as the Pain Probability Index, insights, and recommendations are estimates generated by sensors and software and may be inaccurate, incomplete, or delayed.
Always consult a veterinarian. You are responsible for your dog's health and care. Decisions about your dog should be made with a licensed veterinarian. Do not start, stop, or change any care based only on The Ruff, and seek veterinary help promptly for any concern regardless of what the product shows.
No guarantee of detection. The Ruff may not detect every instance of pain, illness, or injury, and it may indicate a concern when none exists. It is not an emergency, monitoring, or life safety device.
Physical safety. Supervise your dog while they wear The Ruff, check the fit and the skin under the device regularly, and keep the device and small parts away from dogs who chew, since ingestion can be harmful. Discontinue use if you observe discomfort, irritation, or any adverse reaction.
Assumption of risk and limitation of liability+
Assumption of risk. You use The Ruff and rely on its outputs at your own risk.
Disclaimer of warranties. Except for the limited warranty stated below, The Ruff and the Tether service are provided as is and as available, without warranties of any kind, whether express or implied, including any implied warranties of merchantability, fitness for a particular purpose, and non-infringement, to the fullest extent permitted by law.
Limitation of liability. To the maximum extent permitted by law, Tether and its owners, employees, and partners will not be liable for any indirect, incidental, special, consequential, or punitive damages, or for any injury to or death of an animal or a person, any veterinary or other costs, or any loss arising from your use of, reliance on, or inability to use The Ruff or the Tether service. Our total liability for any claim relating to the product or service is limited to the amount you paid for the product.
Indemnification. You agree to hold Tether harmless from claims arising out of your use of The Ruff, your care decisions, or your breach of these terms. Some jurisdictions do not allow certain limitations, so parts of this section may not apply to you.
Limited warranty+
What is covered. Tether warrants that The Ruff hardware is free from defects in materials and workmanship under normal use for one year from the date you receive it.
What we will do. If a covered defect appears during the warranty period, we will repair or replace the device, at our option. Founders Pack orders are not refundable.
What is not covered. This warranty does not cover damage from accident, misuse, chewing or animal damage, unauthorized modification, water exposure beyond the stated IPX7 rating, normal wear, or loss or theft. This warranty gives you specific legal rights, and you may have other rights that vary by location.
Shipping and returns+
Shipping. We currently ship within the United States and Canada. We expect to ship your Ruff in October 2026. This is an estimate and is not guaranteed, and supply chain factors outside our control may move it. You will receive tracking by email when your order ships.
Taxes and duties. Sales tax is calculated at checkout based on your shipping address. For orders shipped to Canada, applicable taxes and any import duties may apply and are your responsibility unless stated otherwise at checkout.
Returns. Founders Pack orders are not refundable. If something is not right with your unit, you may return it within 30 days of delivery for a replacement rather than a refund, provided the device is in good condition. Return shipping and original shipping costs may not be covered. Nothing in this policy limits any right you may have under applicable law that cannot be waived, including for a unit that arrives defective.
Privacy+
What we collect. The Ruff collects sensor data about your dog, including motion, gait, temperature, and sound patterns, along with the device and app information needed to run the service. Sound is processed to recognize patterns such as vocalization rather than to record and keep conversations.
How we use it. We use this data to generate your Pain Probability Index, insights, and recommendations, to operate and improve the product, and to support you.
How we share it. We share information with the service providers who help us run Tether and operate your account. We may also share or transfer information as part of a business sale, merger, financing, or similar transaction, and for other lawful business purposes described in our full privacy policy. Where applicable law gives you the right to opt out of certain sharing, you can do that by contacting us.
Your choices. You can access and delete your data and close your account by contacting us. Full detail is provided in our privacy policy, which governs how we handle your information.
Changes. We may update this notice and our privacy practices at any time and without prior notice, and the current version always applies.
Regulatory and compliance+
The Ruff has not been evaluated or approved by the U.S. Food and Drug Administration, the U.S. Department of Agriculture, or any veterinary regulatory body, and it is not intended to diagnose or treat any condition. This build is a radio device that uses WiFi and Bluetooth Low Energy and contains no cellular radio. It is intended for use in the United States and Canada and is subject to the applicable radio equipment rules for those markets.
Governing law+
These terms are governed by the laws of the State of Delaware, without regard to its conflict of law rules. Any dispute will be resolved in the state or federal courts located in Delaware, unless applicable law requires otherwise. If any part of these terms is found unenforceable, the rest remains in effect.