# Shelly H&T Gen3

*Shelly / S3SN-0U12A*

> The Shelly H&T Gen3 is a Wi-Fi temperature and humidity sensor with an e-paper display. It runs on four AA batteries for about a year or on USB-C power. It suits Google Home, Alexa and SmartThings users through an integration (the maker's cloud). Home Assistant users reach it through an integration (local Wi-Fi control).

- Canonical page: https://smarthomecanon.com/devices/shelly-h-t-gen3
- Last checked: 2026-10-20

## Key facts

| Fact | Value |
| --- | --- |
| Brand | [Shelly](https://smarthomecanon.com/brands/shelly) |
| Category | Temperature and humidity sensor |
| Model numbers | S3SN-0U12A |
| Status | Current[^1][^2] |
| Generation | Gen3[^3] |
| Model code | S3SN-0U12A[^4] |
| Sensing | Temperature and humidity, e-paper display[^4] |
| Power | 4 AA batteries (about 1 year) or USB-C[^4] |
| Radio | Wi-Fi, Bluetooth 4.2[^4] |
| Matter | unknown |
| Local API | HTTP API, MQTT and webhooks[^4][^5] |

## Integration paths

**How the Shelly H&T Gen3 connects**

| Path | Requires | Local | Features lost |
| --- | --- | --- | --- |
| [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 H&T Gen3**

| Path | Platform | Support | Integration |
| --- | --- | --- | --- |
| 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)
- [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 H&T Gen3 List - Shelly Europe shop. https://www.shelly.com/products/shelly-h-t-gen3-1 (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 Gen3 devices - Shelly Knowledge Base. https://kb.shelly.cloud/knowledge-base/shelly-gen3-devices (manufacturer, checked 2026-10-13)
[^4]: Shelly H&T Gen3 - Shelly Knowledge Base. https://kb.shelly.cloud/knowledge-base/shelly-h-t-gen3 (manufacturer, checked 2026-10-13)
[^5]: Shelly Technical Documentation. https://shelly-api-docs.shelly.cloud/ (manufacturer, checked 2026-10-13)