1*Portable Product: Portable product is able to use in any place and any time.It is easy to hold and don"t need complicated equipment that hinders the inspecting and repairing.2*Monitor:2.5" high image resolution monitor enable to show clear image that any place to use.3*Long work fine: Equip with Lithium battery of high capacity .Each 2 hours recharge durable 4.5-5 work hours.4*Humanized design of appearance: 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.5*Support DC power for camera: Its convenient for user to check camera condition and correct direction of camera ,so to make installation and repairing easier.