A straight adapter with an AN12 37-degree male flare and an M16*1.5 male metric thread. M16*1.5 turns up on oil filter housings, cooler take-off plates, turbo drain bosses and gearbox cooler ports, all of which are natural -12 AN territory when you want volume without restriction. Choose this fitting when converting a metric-ported component over to serviceable AN plumbing that can be dismantled, inspected and reassembled. The AN end needs no sealing compound; it relies on the 37-degree flare face and correct torque. The metric end seals against a washer, O-ring or cone depending on the port design, so identify which before assembly.