Check the listing for details. StarPoint Extra Add-On Window / Door Sensor - Model LD - White. Color: White, Condition: New. Listed at 13.47 USD. ••It Is a brand new•• ✅Free Shipping (United States)✅Fast Shipping (Same Day - purchases made until 11am EST)✅Free Returns (30 Days)✅Satisfaction Guarantee If you have any question, please let me know! THANK YOU SO MUCH! Description: StarPoint Extra Add-On Window/Door Sensor - Model LD - White The STARPOINT Expandable Wireless Multi-Unit Long Range Doorbell Alert System Learning Code –L” Series is a CONFIGURABLE and EXPANDABLE doorbell system that can EASILY ADD on 20+ more extra receivers, transmitter buttons, motion sensors and door sensors.CONFIGURABLE and EXPANDABLE doorbell system. Add on or build your own systemEASILY ADD on any number of additional receivers, transmitters, motion sensors or door sensorsLong range operation with the receiver at over 500 feetLook for the –starpoint” symbol for other compatible componentsCE, FCC, RoHS certified.✅ Multiple receivers can be configured to RING WITH DIFFERENT chimes/ringtones to let you know which transmitter was triggered _- a very convenient feature for multiple doorway entries.✅ Built in receiver MEMORY feature RETAINS doorbell chime/ringtone selection even when receiver is unplugged or powered off. Operating range of over 500 ft (1000 ft in open area). 4 levels of adjustable volume from 25db - 110db.✅ Includes 1 extra remote window/door sensor, double sided sticker, AA battery is included.