The RadioRA 3 Sunnata RF Companion Dimmer Switch allows you to expand the use of your RA 3 Sunnata RF PRO Dimmer Switch (RRST-PRO-xx only) and its advanced LED+ dimming technology to create multi-location dimming applications. Up to four Sunnata RF Companion Dimmer Switches can be used with one RRST-PRO-xx - creating five points of dimming control. Tap the switch once for your preset light level, set by your Sunnata RF dimmer switch, and twice for full brightness. Swipe the touch light bar to dim/brighten your lights. The smooth fade on and fade off allows your eyes to adjust comfortably to your determined light level; push and hold for 30 second delayed fade-to-off. Coordinating wall plate sold separately.