how and why to use a “TAPERED” tap (NPT thread) National Pipe Thread
Not all tap and die sets are the same. If you’re working with NPT National Pipe Thread, there’s going to be an actual taper on the tap so when you install your faucet or pipe the thread will get tighter and seal. This is a very important feature if you’re trying to make water-tight plumbing.
taper pipe tap & die set: https://amzn.to/2CEo0Wv
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