Feature:1. Easy Control: The wireless controller enables convenient and flexible remote control on the crane, very useful.2. Wide Utility: Suitable for bridge crane, top cranes, chain cranes, monorails , concrete pump trucks and so on.3. Sturdy Shell: Sturdy ABS shell is very comfortable to hold, which is also waterproof, insulating and durable.4. Working Tips: Needs to use with contactor. Cannot connect directly to the power source since it will damage the motherboard.5. 2pcs Switch: Including 2pcs control switch with clear panel, making the operation much simpler.Specification:Item Type: Crane Remote ControlProduct Material: ABSProduct Model: YU-4STemperature Range: -5-85Radio Frequency Point: 800MHzProtection Grade: IP68Control Distance: Approx. 100meter or 328.08ft (in open environment)Adapter Battery: 2 x 1.5V AA battery (delivered without battery). .Package List:2 x Crane Remote Control1 x Transmitter2 x Protective Cover2 x Fuse1 x User ManualNote:Do not disassemble the product at will, as there may be risks of electric shock.