Sherlo 4 Button Transmitter 403Mhz
Code-Hopping Encryption. Unique antenna design incorporating the keyring. increases operating range by 50%. Crystal frequency-controlled within +/- 100KHz. Frequencies available are 403.55MHz. 12V battery operation - GP23A Alkaline Cell. Typically 2 years battery life expected under normal use. LED flashes when there is a low battery condition. Rubber buttons are easy to press and click positively.