This listing is for a throttle control valve that connects to the engine of a gas powered Rolair air compressor. This is an OEM part directly from Rolair. Below is a list of model numbers that this fits. Some compressors are private labeled for other manufacturers, so it is possible that it will fit additional models to the ones listed.

Models Throttle Control Valve Fits:

4090HK17 Wheeled Gas Compressor
4090HK17/20 Wheeled gas Compressor
6590HK18 Wheeled Gas Compressor
6590HK18/20 Wheeled Gas Compressor