... 1,Size:710mmX160mmX40mm 2,4" red 6 digital led digital clock 100% feedback Led digital clock with computer RS232/485 communication 1 ... 7 Certificate:CEFunction requirement:1, Left 2 digital hours,middle 2 digital minutes,right 2 digital seconds,interval use 4 luminescence led2, ... 32",34",36",38",40" and so on can customized How to choose right?Viewing DistanceThe distance between your led clock and ...