Efreecity 3.5" inch LCD Security CCTV Tester Monitor PTZ Video Audio Camera UTP Tester Portable product is able to use in any place and any time. It is easy to hold and do not need complicated equipment that hinders the inspecting and repairing Monitor: 4.3" high image resolution monitor enable to show clear image that fits any place to use. Hand-hold design for professionals. Easy operation without taking off gloves speeds your works. Clasp ring at bottom fits to all chains and use in all environments : It's convenient for user to check camera condition and correct direction of camera, so to make installation and repairing easier The net line test function: Can carry out can see to turn to show that the net line conjunction circumstance and the net lines link the sequence