Features: RJ45 Cat-5 Cat-5 RJ11 Test: If all cables are working, the lights will turn green from # 1 & # 2 to # 7 & # 8 thereafter. if a light is not lit or lights up non-sequentially, the cables are broken. Automatic scanning mode, quick test, aerodynamic shape is consistent with the design of somatology Durable design, working well even in construction site Super handy device ensures your good mood Cable tester for RJ11, RJ45, 10/100 base-t and telephone cable ... Etc Automatic efficient scanning for missed wiring, mess cable, opening and short circuit Remote test cable up to 1000 feet in length (remote control kit included) 9 led to indicate which wire open or not on the remote unit and master Powered by a DC 9 V battery (not included) Protective switch for low energy consumption