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◉ Product 02 · Bathroom · Drop 01

O-SHIT

A tiny smart sensor that lives behind your toilet and texts you the moment it starts silently leaking — before it wrecks your floor, your ceiling, or your month. Five-minute install. Two-year battery.

$79 ◉ In stock · Ships next day · No subscription

✓

Add a 2-pack — one for each bathroom. $149 total · save $9

Save $9

◉ Fabricatedin Battle Creek, Michigan · ships next business day

◉ Returns30 days, no drama, free return shipping

◉ Warranty1 year on hardware, free battery replacements

◉ Works withiOS + Android app · iMessage + SMS + email alerts

◉ How it works

Three things. Then it never needs you again.

O-Shit is a non-contact ultrasonic sensor. It doesn't touch the water, it doesn't get in the tank, and it doesn't need plumbing. It listens for the specific acoustic fingerprint of a leaking toilet fill valve — and tells on it.

Stick it behind the tank.

Peel off the backing, press the sensor pad against the outside of your toilet tank. It doesn't touch water. Five-minute install. No tools, no plumber.

◉ Install~5 min · adhesive mount

It listens, quietly, forever.

Ultrasonic sensor samples every 30 seconds, matching the pattern of normal flushes against a leaking fill valve. Learns your toilet's baseline in the first 48 hours.

◉ Sample rate30s · on-device ML model

When your toilet lies to you, it texts.

If O-Shit detects a running fill valve for >60 seconds without a real flush, it sends an iMessage, SMS, or push. Usually weeks before you'd notice the water bill.

◉ Alert latency<90s · audible + app

◉ Why this sensor

Six things it does that a $20 leak puck can't.

We did not invent the water sensor. We made a better one. These are the things most cheap leak detectors miss, and most expensive ones charge you $12/month to access.

No plumbing required.

The sensor is external — it reads the tank through the porcelain. You don't need to shut water off, don't need to know what a shut-off valve is.

No subscription.

Buy it, set it up, get alerts forever. We don't hold your notifications hostage. The app is free, the sensor is yours.

Works offline.

Bluetooth direct to your phone when your router is down. You'll still get the audible alarm at the unit and the SMS when your phone reconnects.

2-year battery, free replacements.

CR2032 coin cell, 24+ months per battery in normal use. When it's low, we ship you a replacement, free, before it dies.

Learns your toilet.

On-device model adapts to your exact flush profile in 48 hours. False-positive rate is <1 alert/year based on Drop 01 testing across 312 homes.

Good names for bad news.

Push notifications that tell you exactly what's happening: "O-Shit · Tank #2 has been running for 4 min. Check the flapper." Zero branding jargon.

◉ Spec sheet

The receipts.

Engineered and assembled in Battle Creek. FCC-tested, RoHS-compliant, and nobody gets your data except you and the aggregated false-positive rate we publish quarterly.

Dimensions72 × 38 × 18 mm · 2.8 × 1.5 × 0.7 in

Weight34 g · 1.2 oz

SensorDual ultrasonic · non-contact · 40 kHz

Sample rateEvery 30 seconds · continuous

ProcessingOn-device ML · no cloud required

ConnectivityWi-Fi 2.4 GHz + Bluetooth 5.2

BatteryCR2032 · 2-year life · replacements free

AlertsPush + SMS + email + iMessage + audible at unit

AppiOS 15+ · Android 10+ · Siri + Alexa routines

InstallAdhesive mount · no plumbing · ~5 min

Mount pad3M VHB · removable · residue-free

CertificationsFCC ID 2A-OS01 · RoHS · REACH

Data privacyZero data sold · zero tracking · export on request

Made inBattle Creek, Michigan, USA

Warranty1 year hardware · lifetime support

◉ Install

Four steps. No plumber.

Takes longer to open the box than to install the device. If you've ever stuck a Command hook to a wall, you've already passed the skill test.

◉ Download the app

iOS or Android. Create an account. No credit card, no upsell, no 12-step onboarding.

◉ Peel and stick

Wipe the tank dry. Peel the 3M VHB backing. Press the sensor against the back of the tank for 20 seconds.

◉ Pair it

Hold the sensor button for 3 seconds. App auto-detects, connects to your Wi-Fi, done.

◉ Flush twice

Two normal flushes train the sensor to your toilet's baseline. You're live in under 5 minutes total.

◉ Compared

Us vs. the puck.

The $20 leak puck on Amazon solves a different problem — water already on your floor. O-Shit tells you before water gets anywhere. Here's how that plays out spec-to-spec.

Feature

O-Shit · $79

Leak puck · $20

Whole-home · $500+

Detects silent toilet leaks

Yes · before water hits the floor

No · only when water spills

No · monitors flow, not acoustic

Install time

~5 min · adhesive

~10 sec · drop on floor

Licensed plumber · $200+

Alerts

Push + SMS + email + audible

Local alarm only

App-based

Subscription required

No — ever

$8–$15 / month

Battery life

2 years · free replacements

~6 months

Hardwired

Made in

Battle Creek, MI

Shenzhen

Varies

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◉ Common questions

O-Shit, explained.

Does it really work without touching water?

Yes. The sensor is an external ultrasonic pickup that reads vibration and acoustic pattern through the porcelain of the tank. Running fill valves produce a very specific signature. It doesn't need to see water to hear water.

How do I know it fits my toilet?

If your toilet has a standard tank behind it (99% of residential toilets sold in the US in the last 40 years), O-Shit fits. We tested Drop 01 across American Standard, Toto, Kohler, Duravit, and some 1950s vintage — all passed. Exception: wall-hung tankless toilets, where there's nothing to stick it to.

What's the false-positive rate?

<1 alert per year in the Drop 01 test cohort (312 homes, 180 days). If we ever ship a firmware update that raises it above 2/year we'll let you opt out of the update, or refund you. The model is on-device, so no, you're not training our servers.

Do I need Wi-Fi?

Not for alerts. The sensor works over Bluetooth direct to your phone. Wi-Fi is optional — it just means you'll get alerts when you're away from home. Audible alarm at the unit works regardless.

Can I install it in a rental?

Yes. The 3M VHB pad removes cleanly with a hair dryer and a plastic card — no residue, no damage. Bring it with you to the next place.

Do I really need this?

The EPA estimates a silent toilet leak wastes 200 gallons per day — roughly $20/month on most water bills, and a leaky fill valve can also warp subfloor or stain ceilings below. O-Shit pays for itself in about 4 months of catching one leak. If you've ever had a water-damage claim, also consider that your deductible is probably more than $79.