Specification: Brand new Transmitter Size: Approx. 75X51X20mm Receiver Size: Approx. 95X65X24mm Type: Doorbells Ringtones:38 pcs DIY Supplies: Electrical Doorbell Type: Wireless Power Source: AC,Battery Model Number: A10BB Power supply: 110V-220V-240V Working frequency: 433MHZ Ring Tone: 38 ring tones Certificate: CE,FCC,Rohs Waterproof : yes Power Source: Plug EU US UK Volume:3 files(can be mute) 0-85db Battery mode: 12v 23A battery (not include battery) Receiving distance: 300M Remote (in open area) Suitable for: Home,office,villa,hospital,school,factory The transmitter 12V23A battery factory pre-installed (not include battery) The use of microprocessor control, double-sided PCB micro-power design. The frequency of 433MHz, can be customized other frequencie. Touch the button configuration, superheterodyne learning code on the code mode. The transmitter without screw chuck design to achieve waterproof and dustproof. Double-sided stability of the PCB, the chip standby sleep up to micro-level. Package Included: 1 * Outdoor Transmitter 1 * Indoor Receiver