What's the meaning of the oil filter thread M 20 X 1.5 3/4-16?
3/4-16 is American Standard unified thread, the formal dimension should behind UNF-2B, the major diameter of the thread nominal size of 3/4 inches per inch (25.4 mm) of 16 teeth.
This is the common connection thread of the screw type filter
M 20 X 1.5 metric threads, nominal size of large thread 20 mm, pitch 1.5 mm,
