To suit 1/10 scale model car or truck shells. This is a direct roof mount so will need a few holes drilled in the center roof of your shell plus one larger hole for the wires to feed through. This is powered by either a direct 6v input (no batteries included) or by a spare port on your receiver. The connector type is male JR. Note: Input by a voltage higher than 6v DC will damage the unit. Light bar measures 68mm x 13mm between fixing points (rectangle). A 10mm hole is required on each side between the fixing points for the wire to feed through. Simple 1 page instructions included to help with fitting.