This billet aluminum oil cap for the Gen 2 Mazdaspeed valve cover is threaded for a 10an ORB fitting and allows you to vent your crankcase pressure to a vented or sealed and recirculated catch can setup.

Below are links to recommended fittings that allow you to have a tight 90 off the cap to the line setup of your choosing. The first link is the fitting pictured on the oil cap. Its main feature is that it free spins 360 degrees so you don’t have to remove the line from the cap in order to take the cap off for oil changes. Though, any 10AN ORB fittings of your choosing will work on this cap.

Swivel 10AN ORB to 10AN male by Raduim

Swivel 10AN ORB to Hose End by Racetronix