M18x1.5 thread tap is used to cut internal metric fine threads in drilled holes. It is suitable for both repairing damaged threads and creating new threads where components with M18x1.5 thread need to be mounted.
M18 indicates the nominal thread diameter of 18 millimetres, while 1.5 indicates the thread pitch of 1.5 millimetres. This means that the distance between each thread crest is 1.5 millimetres, giving a finer thread compared to standard metric coarse thread.