---
product_id: 304912617
title: "Water Leak Sensor 2,1/4 Mile World'S Longest Range Smart Home Sensor,Water Detector With Built-In Siren Up To 105Db,Works Alexa And Ifttt-Yolink Hub Required,Ys7904-Uc"
brand: "yolink"
price: "HK$471"
currency: HKD
in_stock: true
category: "Yo Link"
url: https://www.desertcart.hk/products/304912617-water-leak-sensor-2-1-4-mile-worlds-longest-range
store_origin: HK
region: Hong Kong
---

# 1/4 mile LoRa range Real-time smartphone alerts 105dB built-in siren Water Leak Sensor 2,1/4 Mile World'S Longest Range Smart Home Sensor,Water Detector With Built-In Siren Up To 105Db,Works Alexa And Ifttt-Yolink Hub Required,Ys7904-Uc

**Brand:** yolink
**Price:** HK$471
**Availability:** ✅ In Stock

## Summary

> 💧 Stay dry, stay ahead—never miss a leak with the world’s longest-range water sensor!

## Quick Answers

- **What is this?** Water Leak Sensor 2,1/4 Mile World'S Longest Range Smart Home Sensor,Water Detector With Built-In Siren Up To 105Db,Works Alexa And Ifttt-Yolink Hub Required,Ys7904-Uc by yolink
- **How much does it cost?** HK$471 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.hk](https://www.desertcart.hk/products/304912617-water-leak-sensor-2-1-4-mile-worlds-longest-range)

## Best For

- yolink enthusiasts

## Why This Product

- Trusted yolink brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Instant Flood Alerts:** Receive real-time notifications via app, SMS, or email to stop water damage before it starts.
- • **Powerful Built-In Siren:** 105dB siren ensures immediate on-site awareness, even if you’re away.
- • **Unmatched Long-Range Coverage:** Industry-leading 1/4 mile wireless range powered by LoRa tech—perfect for basements, garages, and remote outbuildings.
- • **Seamless Smart Home Integration:** Works effortlessly with Alexa and IFTTT for next-level automation and control (YoLink Hub required).
- • **Effortless Setup & Versatile Placement:** Compact, battery-powered design installs in minutes near sump pumps, dishwashers, or fish tanks—protect every vulnerable spot.

## Overview

The YoLink Water Leak Sensor 2 offers the longest wireless range in the market at 1/4 mile using LoRa technology, combined with a loud 105dB built-in siren and real-time smartphone alerts. Designed for indoor use, it monitors water presence or absence in critical areas prone to leaks or flooding. Compatible with Alexa and IFTTT (YoLink Hub required), it provides smart home integration and early-warning notifications to prevent costly water damage. Powered by 2 AAA batteries and easy to install, it’s ideal for basements, garages, laundry rooms, and remote outbuildings.

## Description

INTRODUCTION:Smart water detector with built-in siren, detects the presence or absence of water, and displays the status on the YoLink appNote: For water detection, only, without an integral siren, consider our original Water Leak SensorREQUIREMENTS:YoLink Hub with internet connection (wired Ethernet or 2.4GHz Wi-Fi). Please search B07TQLKQLJ for the HubSmartphone or tablet running iOS 9 or higher, Android 4.4 or higherTECHNICAL SPECS:Power: 2 AAA batteries (3V DC)Dimension [L x W x D]: 2.44 x 2.44 x 0.80 inches (83.06 x 30.99 x 14.99 mm)Cable Sensor: 4.2 feet (1.2 meters), can be extended to 10 feetOperating Temperature Range: 32°F – 122°F (0°C – 50°C)Operating Humidity Range: ≤95%RH non-condensingIntended for indoor use only APPLICATIONS:Place the YoLink Water Leak Sensor 2 anywhere that is at risk of high moisture or water, due to leaks or floodingUse the YoLink smartphone app to remotely monitor the status of your water leak sensors in your home, rental property, condo, summer home or business (internet connection and YoLink Hub required) YoLink’s industry-leading long range communication allows for placing the sensor in your barns, separate garage building, greenhouse, etc.Some common applications include:Locations at or below grade, subject to water incursionBasement floorsNear sump pumpsUnder sinksNext to toiletsUnder or near laundry machinesUnder dishwashersUnder refrigerators & ice machines Under fish tanks/aquariumsInside hot tubs**Refer to device environmental limitations in Technical Specs, above. Use this device outside the recommended ranges at your own risk; warranty may be voided, etc.PACKAGE CONTENTS:(1) YoLink Water Leak Sensor 2 (batteries included)(1) Cable Sensor(1) Mounting Hook(1) Quick Start Guide PLEASE NOTE:YoLink products work only in the USA and Canada

## Features

- Smart Water Leak Detector: Monitor critical locations at risk of flooding, and be informed immediately of the presence of water, preventing costly repairs; Smart Water Level Monitoring: The sensor may be configured for water level monitoring – be informed when water is no longer present or when water levels recede. Monitor water supplies for pet care, house plants, gardening and more.
- World's Longest Wireless Range: Powered by LoRa technology, the long-range yet low-power system offers the industry’s longest receiving range in the market (1/4 mile). Our long-range coverage enables its use in areas challenging for most residential Wi-Fi systems, such as basements, outdoor porch/patio areas, sheds, free-standing garages, even remote outbuildings on your property.
- Early-Warning Notifications: Receive real-time early-warning notifications and protect your home and property from water damage. Notifications are in the form of smartphone banner alerts, limited SMS/text messages and emails, each optional and configured per your needs. Additionally, you may configure your system to activate a siren alarm and/or lights in your home.
- Easy and Effective Property Protection: The YoLink wireless Water Sensor could not be easier to install; just place near or under the equipment you wish to monitor. Suggested uses are near or under sump pumps, toilets, water heaters, laundry machines, dishwashers, sinks, fish tanks and any other location subject to water leaks and flooding.
- From Simple to Super-Smart: After setting up your notification preferences, keep it simple and let the YoLink system do the rest and monitor your home and property for you. Or, utilize available advanced automation features, including 3rd-party integration with Alexa and IFTTT, to interact with other YoLink and 3rd-party smart devices. Limited only by your imagination! (YoLink Hub is required, sold separately; Please search B07TQLKQLJ for the Hub)

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B08P1WD66X |
| ASIN  | B08P1WD66X |
| Batteries  | 2 AAA batteries required. (included) |
| Best Sellers Rank | #67,288 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #197 in Safety Sensors & Detectors |
| Brand Name | YoLink |
| Customer Reviews | 4.5 4.5 out of 5 stars (442) |
| Customer reviews | 4.5 4.5 out of 5 stars (442) |
| Date First Available  | 3 April 2021 |
| Item Dimensions | 8.3 x 1.5 x 3.1 centimeters |
| Item model number  | YS7904-UC |
| Lower Temperature Rating | 32 Degrees Fahrenheit |
| Manufacturer | YOSMART |
| Manufacturer  | YOSMART |
| Measuring Range | 32 - 122 °F |
| Model | YS7904-UC |
| Mounting Type | Tabletop Mount |
| Part Number | YS7904-UC |
| Product Dimensions  | 8.31 x 1.5 x 3.1 cm; 100 g |
| Sensing Distance | 0.25 Miles |
| Smart Home Compatibility | Smart Home Compatible |
| Specific Uses For Product | water leak detection, basement, outdoor, remote outbuildings, sump pumps, sinks, toilets, laundry machines, dishwashers |
| Style Name | Water Leak Sensor 2 |
| UPC | 850024791091 |
| Upper Temperature Rating | 122 Degrees Fahrenheit |

## Product Details

- **Brand:** YoLink
- **Item dimensions L x W x H:** 8.3 x 1.5 x 3.1 centimeters
- **Lower temperature rating:** 32 Degrees Fahrenheit
- **Measuring range:** 32 - 122 °F
- **Style:** Water Leak Sensor 2

## Images

![Water Leak Sensor 2,1/4 Mile World'S Longest Range Smart Home Sensor,Water Detector With Built-In Siren Up To 105Db,Works Alexa And Ifttt-Yolink Hub Required,Ys7904-Uc - Image 1](https://m.media-amazon.com/images/I/51xkkGlZDWL.jpg)

## Questions & Answers

**Q: Does the entire cable detect water or just the tip on the end?**
A: The sensor cable of the YoLink Water Leak Sensor 2 detects water along the length of the cable. For more information, please kindly refer to the following guide http://www.yosmart.com/support/YS7904-UC/docs/instruction

**Q: I plan to submerge v3 type of the sensor in the sump pump. I wonder if the "dirty" water will corrode/damage the sensor?**
A: It is possible for the probe cable to get a build-up that can slow the response time, particularly slow drying (as the gunk on it might hold moisture). For this application, I recommend wiring our sensor to a float switch. It will work great, even in a dirty water environment. 

We do not suggest any particular model. Most of them are interchangeable by flipping the float around 180° but you want one that has closed contacts when in the water-detected/high position, for it to give you a "water detected" indication on the app. It is possible to work with the opposite (open) and get the desired response and notifications in automation settings but the app will display it as no-water when you have water at the float. 

Eric with YoSmart

**Q: How many sensors can i "pair" with one hub? i have 3 basements that i need to monitor. or do i need a hub for each sensor?**
A: 128 pairs!

You will need a hub at each building, but unless you have a very large building, or a lot of RF obstructions, you should be fine with just one hub. 

Eric with YoSmart

**Q: Will laying this cable on a conducting metal surface trigger the alarm? I.e. inside a water heater pan?**
A: No, the metal will not impact its operation. Do keep in mind, the sensor body should not get wet. That has to stay outside the pan. You might consider instead our Water Leak Sensor 1. You can look at customer-submitted photos and find several instances of this sensor being placed in a water heater or air conditioner pan. 

https://www.amazon.com/dp/B07Z7QWJBP?ref=myi_title_dp&th=1

## Frequently Bought Together

- YoLink Water Leak Sensor 2,1/4 Mile World's Longest Range Smart Home Water Leak Sensor,Water Leak Detector with Built-in Siren Up to 105dB,Works with Alexa and IFTTT-YoLink Hub Required,YS7904-UC
- YoLink 10 Foot Sensor Cable Water Leak Sensor 2

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*Product available on Desertcart Hong Kong*
*Store origin: HK*
*Last updated: 2026-07-23*