I have a 1 3/8 copper tube drain pipe coming out of the wall and 1 1/4 p-trap chromed copper I understand that the 1 3/8 is actually nominal size for 1 1/4 tubing but I need to know how to step it down to a 1 1/4 inch for my drain size? Its also exposed so would like to make it look clean.

Hi Diver

It sounds like you have an 1.25" copper pipe sticking out of the wall and that you have an 1.25" SWEAT chromed PTRAP. If this is the case, then you need to solder the PTRAP onto the copper pipe... PTRAP slides over the copper and gets soldered.

That sound about right?