It`s apparent that a couple of u guys don`t know pipe sizes at all. The last pic has the treaded portion of the fitting, the same size as the hose side. No way 1/4" pipe is the same diameter of a 1/2" hose or fitting ! Done w/ this ----------------
Please read my posts again - at no time did I refer to the nipple as a "1/2" pipe nipple". It is a hose nipple that fits in a 1/4" NPT hole (ie has a 1/4" pipe thread) and has an OD of 1/2". Like I said.
My temp sender has a 1/8" pipe thread and sits in the 1/8" NPT hole.
The table in post 31 illustrates the various pipe thread sizes and corresponding OD's.
I gave the OP the exact answer he was looking for. With pictures.