SB-3S-Bell-XS RF Intelligent Door Bell and Access Reader RF Intelligent Door Bell and Access Reader, With Room/Apt Number Back Lit, Built in Card Proximity Reader, and Door Release Relay Controller, Magnetic Contact Input for door Status Monitoring, Capacitive Touch Technology, Elegant Crystal Glass Finish, Functions: (DND, Clean Room, and Pick Laundry indicators). Parameters Model SB-3S-Bell-XS SKU 421121 Bus Power 45 mA Width 105 mm Height 170 mm Depth 40 mm Weight 361 g Material CustomOne CustomTwo CustomThree CustomFour CustomFive Discount category A Price category 5.32-4 32 pcs in stock in stock in stock You can buy these goods through registered HDL partner. Question to product