When it comes to breather and overflow tanks, STEF’S doesn‘t fall short in selection! Originally designed as external dry sump tank breathers, STEF’S tanks can also be used as crankcase, transmission, and rear-end vent tanks. We also list an air/oil separator which has become an essential addition to any crankcase evacuation system. The tanks listed include a universal mounting bracket, male AN or NPT fitting, drain cock, and either a breather or 2" twist off lid.