Upgraded Cap For Mocal Oil Catch Tank Orange CTBC1 With Foam Filter Element. A direct replacement for the breathable cap supplied with Mocal Oil Catch Tanks Utilises a Foam Filter element installed internally in the cap above the splash guard to prevent oil passing the cap whilst allowing the gases to flow freely. Resolves common issue of oil vapours condensing on the top of the catch tank which is often messy and annoying Also available in black in another listing on my page