In article , wrote:

Not sure what you're calling "mending couplers"--you mean pipe unions or
other threaded connector, I assume?

I imagine he means an RP coupling. These don't have a center flange or nub, so
they can slide completely on to a pipe. Very useful when you don't have enough
clearance to separate the ends of a joint enough to put a standard coupler in.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?