The ST01 Series In-Wall Timers are easy-to-program, 4-button programmable timers that allow up to 40 event settings per week. The timers have an Astronomic feature for sunrise and sunset switching.FEATURES:- Easy to program for 24-Hour or 7-Day load control- Auto Daylight Saving Time adjustment- CFL/LED compatible- Astronomic feature provides sunset ON and sunrise OFF settings or combine Astronomic features with specific timed ON/OFF programming- Low battery indicator- Continuously displays time of day, mode and load status- CR2 lithium battery provides up to 2+ years of time keeping without AC power- Replaces single-pole or 3-way switches in a variety of applications- Random setting feature available to avoid predictable time controlled look- User program selections are stored in non-volatile memory- Controls all voltage/frequencies with no adjustments required- No neutral required- Manual override feature