It is a very popular smart home product, good looking with touch panel. With this product, you can control your lights via 3 methods, touch the panel, wireless control via smart life APP or voice control via alexa or google home. It is a  US standard smart switch with wide working voltage AC100-250V.
US standard maybe suitable for America countries, Australia and New Zealand, Vietnam, Thailand and so on. please check if US size is suitable for your country before purchase or feel free to contact us for help.
You can easily use the wifi switch when you get the product, you can install the wifi switch according the wiring like the follow picture, sure the manual also have the wring and operation steps. 
1. Achieve 3 methods to control the lights
- touch control, app remote control and voice control
2. Sensitive touch panel
- sensitive touch control like smart phone touch 
3. Toughened glass
- it's easy to clean and always looks new
4. App control distance
- anywhere you want via app remote control.
5. LED indicator
- with red and green LED indicator, distinguished in the darkness. Red is light on, green is light off.
6. APP support
- smart life or tuya smart app 
7. Timing
– Set scheduled/countdown timers to turn on/off at specified time.
8. Share Control
– Control your smart home together with your family.
9. Voice Control
– Works perfectly with Alexa, Googl home
10. Scene control
- One-key-control for multiple devices
10. Neutral required
- Neutral line and live line wiring for stable performance 
11. Network support
- Control electronic devices over 2.4G Wi-Fi and 2/3/4G mobile network is available
12. Standard type
- 120mmx74mmx38mm America size. 
13. Application
- Suitable for common lamps, such as incandescent, fluorescent lamps, led lamps

3 gang wifi smart light switch ( alexa google enabled)