Use this fitting to connect your -4AN turbo oil feed line to your oil filter flange. VW/Audi vehicles use M10x1 threaded plugs and sensors on the oil filter flange. This fitting takes the place of either providing a leak-free connection for your oil feed line.
Beware of other oil feed line adapters on the market! 1/8" NPT threads are NOT compatible with M10x1. Using a 1/8" NPT feed line adapter on your oil filter flange will permanently damage the threads. If it doesn't say M10x1 it's not!