Black cap. Touring models have the oil tank mounted under the transmission. The engine; with two massive pistons going up and down; breathes in to the oil tank. This system is a way to vent the oil tank to help reduce pressure build-up and reduce power robbing pressures and stops dipstick blow-out. Comes as complete kit with filter; braided clear PVC covered lines and; if required; gaskets. Note: Gaskets are supplied where required. Note: Must replace the factory vent line from back of engine to oil filler spout.