42 Draft Designs PCV Threaded Fitting 3/4" Plastic is specifically designed for use in your VW or Audi vehicle. This fitting is used to make connections in your oil catch can PCV tubing. An agressive barb on one end holds 3/4" ID tubing tight. 1/2" NPT male threads on the other end allow threaded connection to any 1/2" NPT port. Hose clamps are recommended but not required. This fitting is injection molded from a glass filled nylon polymer - the same material VW uses to make their plastic coolant, fuel, and PCV fittings. This fitting is tough, oil resistant, and black!