Two pieces FULL RANGE DIMMING – Give your space the perfect amount of light with the ability to customize the brightness levels from 0 to 100%. Works ONLY with dimmable bulbs and lamps. WIRELESSLY CONTROL & SCHEDULE LIGHTS AND OTHER DEVICES – Schedule timed events for connected devices. Customize scenes for day or night, home or away. Wirelessly control switch from anywhere through your smartphone, tablet, PC or Z-Wave remote. Switch can be operated manually. ALEXA COMPATIBLE (HUB REQUIRED) - Requires an Alexa supported hub for voice control with Amazon Echo Products (Alexa device and hub are sold separately). Cannot connect directly with ECHO PLUS (Only ZigBee products can connect directly to Echo Plus). REQUIRES A Z-WAVE CERTIFIED HUB - Compatible with the following Z-Wave Hubs: Honeywell, Ring, SmartThings, Wink, HomeSeer, Fibaro, Trane, Nexia, ADT, Vera, and more. IN-WALL INSTALLATION WITH HARD WIRED CONNECTIONS (NEUTRAL WIRE REQUIRED) – Replace your existing in-wall switch in as little as 15 minutes.