Material:the double power transmission switch is made of high-quality flame-retardant plastic material, which has good insulation, high temperature resistance and safety and reliability Silver contacts:This automatic transmission switch has silver contacts that are used for movement and static charging, and significantly improves the conductivity and life of the product Advantage:If the normal power supply is not normal, the emergency power supply works immediately to the continuity of the power supply This automatic transmission switch has a built-in signal output port with normal standby opening that can be connected to the signal display This automatic switch with double power has a small size and good performance, is easy to carry and store and convenient to use Colour:As Shown Material:plastic Package Contents: 1 * Transmission Switch Only the above package content, other are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.