... high performance laser source for field test and lab project development. With features of durable structure, large LCD display with backlight ... network installation, trouble shooting, maintenance and other optical fiber related systems. It can be widely operated for LAN, WAN, CATV, ... NI-MH rechargeable battery or 9V dry battery, LCD display Batteryworking duration (h)4 hoursLow voltage warning≤7.2V ...