The provided fitting is the same size as the rad hose on one end, and is threaded for an AN fitting on the other end. The swivel neck comes pre-assembled with a quality thermostat (180 deg °F) which is held in place with a 'C' clip. Adjustable, set the rad hose at any angle. The housing swivels, allowing you to position the water outlet angle before it is tightened down. Fan switch port for engine swaps and easily deletes heater core hoses on race cars; threaded water outlet for custom setups; uses a standard size thermostat that can be replaced with anything in the (160-195 °F) degree range.