Two-way FM Car Alarm Systems with Diamond Film Glass and High Light Emerald Green LCD Backlight Carrier modulation: FM-FM Remote transmission distance to main unit around 1000m Remote feedback range to transmitter up to 1500m Key lock function to protect pressing keyboard by mistake Diamond film glass lens for ant-scratch Extra high light emerald green LCD back light Two-way feedback confirmation, everything is under control Blue super bright LED indicator Trunk release (need add relay) Basic alarm function same as one way car alarm Can add stat module Accept Redesign by customer Double side PCB, full SMT technology One transmitter or two transmitter