"Brian Sharrock" wrote:


Assuming that NSPM is National Pipe Standard _Male_
then one might need a BSP(parallel) ... ?

National Pipe Straight Mechanical - similar in thread form and
threads per inch to BSPP except at small diameters.

Luckily In 1/2" size the threads per inch are the same but there is a
slight difference on the thread OD 13/16" for BSPP and 27/32" for NPSM
which for all practical purposes will make bugger all difference.

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