For restaurant use、 this wireless transmitter button is typically placed on or attached to each table. When a guest wants his or her server、 he/she presses the button of a service bell、 which sends a signal to the central receiver. This transmitter adopts learning code chip、 it can be used with any of the 433MHz receivers in our store. Features:Small、 compact size、 low current drawRF frequency: 433MHzModulation Mode: ASK (AM)Working chip: learning codePower: 12V/23A battery (included)Working current: 17mAEmission Distance: 500m (open area)Working temperature: -20＜C to 55＜CSize: 60 x 60 x 20mm / 2.3 x 2.3 x 0.7 inWeight: 42g / 0.09lbWith a base and double-sided adhesive、 it can be fixed on the tableApplications:Tea or coffee house、 spas and salons、 health and fitness Clubs、 restaurants、 hotel conference rooms、 executive dining rooms、 Saloon、 nightclubs、 bowling alleys、 massages house、 churches、 casinos、 golf and country clubs、 hospitals、 health clubs、 and offices. Package Include:1 x Button Transmitter1 x Base1 x Double-sided adhesive