# Shelly Flood Gen4

*Shelly / S4SN-0071A*

> The Shelly Flood Gen4 is a battery-powered water leak sensor with a 2 m leak sensor cable that extends to 150 m. It has Matter over Wi-Fi by default and Zigbee as an alternate firmware. It suits Home Assistant users, with native support through Zigbee. Google Home, Alexa and SmartThings users reach it through an integration (the maker's cloud).

- Canonical page: https://smarthomecanon.com/devices/shelly-flood-gen4
- Last checked: 2026-10-20

## Key facts

| Fact | Value |
| --- | --- |
| Brand | [Shelly](https://smarthomecanon.com/brands/shelly) |
| Category | Leak sensor |
| Model numbers | S4SN-0071A |
| Status | Current[^1][^2] |
| Generation | Gen4[^3] |
| Model code | S4SN-0071A[^4] |
| Sensing | Water, through a 2 m leak sensor cable (extendable to 150 m)[^4] |
| Power | 4 AA batteries (about 2 years)[^4] |
| Radio | Wi-Fi 6, Bluetooth 5, Zigbee[^4] |
| Matter | withheld |
| Local API | HTTP API, MQTT and webhooks[^4][^5] |

## Integration paths

**How the Shelly Flood Gen4 connects**

| Path | Requires | Local | Features lost |
| --- | --- | --- | --- |
| [Matter / Wi-Fi](https://smarthomecanon.com/protocols/matter-wifi) | withheld | unknown | unknown |
| [Zigbee](https://smarthomecanon.com/protocols/zigbee) | Zigbee coordinator[^4] | unknown | unknown |
| [Wi-Fi local](https://smarthomecanon.com/protocols/wifi-local) | withheld | withheld | unknown |
| [Wi-Fi cloud](https://smarthomecanon.com/protocols/wifi-cloud) | Vendor cloud account[^4] | No[^4] | unknown |

**Platform support for the Shelly Flood Gen4**

| Path | Platform | Support | Integration |
| --- | --- | --- | --- |
| Zigbee | [Home Assistant](https://smarthomecanon.com/platforms/home-assistant) | withheld | zigbee2mqtt |
| Wi-Fi local | [Home Assistant](https://smarthomecanon.com/platforms/home-assistant) | withheld | Shelly |
| Wi-Fi local | [Homey](https://smarthomecanon.com/platforms/homey) | withheld | cloud.shelly.control |
| Wi-Fi cloud | [Amazon Alexa](https://smarthomecanon.com/platforms/alexa) | Via integration[^4] |  |
| Wi-Fi cloud | [Google Home](https://smarthomecanon.com/platforms/google-home) | Via integration[^4] |  |
| Wi-Fi cloud | [Samsung SmartThings](https://smarthomecanon.com/platforms/smartthings) | Via integration[^4] |  |

## Related pages

- [Shelly sensors](https://smarthomecanon.com/lines/shelly-sensors) (line)
- [Shelly](https://smarthomecanon.com/brands/shelly) (brand)
- [Matter over Wi-Fi](https://smarthomecanon.com/protocols/matter-wifi) (protocol)
- [Zigbee](https://smarthomecanon.com/protocols/zigbee) (protocol)
- [Wi-Fi with local control](https://smarthomecanon.com/protocols/wifi-local) (protocol)
- [Wi-Fi through a cloud service](https://smarthomecanon.com/protocols/wifi-cloud) (protocol)
- [Home Assistant](https://smarthomecanon.com/platforms/home-assistant) (platform)
- [Homey](https://smarthomecanon.com/platforms/homey) (platform)
- [Amazon Alexa](https://smarthomecanon.com/platforms/alexa) (platform)
- [Google Home](https://smarthomecanon.com/platforms/google-home) (platform)
- [Samsung SmartThings](https://smarthomecanon.com/platforms/smartthings) (platform)

## Sources

[^1]: Shelly Flood Gen4 - Shelly Europe shop. https://www.shelly.com/products/shelly-flood-gen4 (manufacturer, checked 2026-10-13)
[^2]: Shelly Europe shop catalog (Shopify product feed, pages 1-4). https://www.shelly.com/products.json?limit=250&page=1 (manufacturer, checked 2026-10-13)
[^3]: Shelly Gen4 devices - Shelly Knowledge Base. https://kb.shelly.cloud/knowledge-base/shelly-gen4-devices (manufacturer, checked 2026-10-13)
[^4]: Shelly Flood Gen4 - Shelly Knowledge Base. https://kb.shelly.cloud/knowledge-base/shelly-flood-gen4 (manufacturer, checked 2026-10-13)
[^5]: Shelly Technical Documentation. https://shelly-api-docs.shelly.cloud/ (manufacturer, checked 2026-10-13)