Danny,

I don't think I have heat saver nipples. I just checked. All that I
can see coming out of the female couplings on the tank are what look
like short, standard nipples.

You may not be able to tell from looking at the outside of the pipe. Mine
just looked like short galvanized pipe nipples, except for little arrows
stamped on the sides to show the directional flow. You couldn't see the
little flappers inside until the supply lines were disconnected.

Anthony