Dual Switch: With the multi-switch function, you can control 1 device using 2 independent switches. Wireless, Easy Installation: No wiring needed between the switch and receiver/switch and light. Traditional switches can be directly replaced by this unit (sticker included). Long-Distance Signal Transmission: The effective range between transmitter and receiver is approximately 0-40 meters (effective through 1 wall) for indoor use, and 400 meters for outdoor use. (Note: Do not install the switch on a metal surface or the receiver in a metal enclosure, as this may interfere with wireless signals). Battery-Powered Switch, Long Lifespan: The switch is rated for 600,000 presses, and the CR2032 lithium battery can last 6-8 years. The battery is replaceable. Note: 1. The signal can pass through 1 wall, but not through an iron wall. This switch does not have a dimmer function. The switch is waterproof, but the receiver (size: 4 x 2.5 x 2.3 cm) is not waterproof. It can be placed in a canopy, junction box, or connection box.