The Wattstopper DSW-301-W-U is a commercial-grade dual-technology wall switch occupancy sensor rated at 120/277 VAC that replaces standard wall switches and fits behind a decorator wall plate for in-wall installation. Combining PIR and 40 kHz ultrasonic detection across a 180 field covering up to 1,050 sq ft, it supports selectable Auto/Manual-ON operation, DIP-switch time delays of 5/15/30 minutes, adjustable light level sensing (8180 fc), walk-through mode, and a selectable audible alert for impending shutoff. Listed to UL, cUL, FCC Part 15, RoHS, and BAA compliant; USA manufactured; 5-year warranty. White finish.