Don't think I've seen a female thread one before, the trouble you'll have is being able to dig the old one out enough to cut the threads then wind...
Price seems fine to me.
You can drill a hole a hole 25% of the size of the joist between 0.25 and 0.4 along the span of the joist.
Nightmare customer right here.
Is it easy to swap this for a key lock on the outside with a thumb turn on the inside?
How did you expect him to connect the pipes to the radiators without cutting the floor?
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