1Automatic backlighting. Dual frequency standby. Timeout timer. Voice prompts. 2DTMF emergency alarm, channel lock function, emergency SOS sound and light alarm. 3PC software or manual program, steganographic scanning function, FM radio receiver (65Mhz-108MHz). 4Confirm forwarding (1750Hz), low battery warning, display illumination and programmable keyboard. 5Dual frequency, dual display, IP67 waterproof and dustproof. Up to 128 memory channels. Cross band reception / transmission.