Yescom Wireless Home 433MHz Door Window Security Sensor System Accessory Alarm Switch Transmitter Voltage: DC 12V Dimension: 2-3/4" x 1-3/8" x 5/8" Transmitting Frequency: 433 MHz Transmitting Distance: 328ft(without Block) Effective range of magnetron: pick up 19/32", release 1-3/16"