Although this kit contains several fittings, tees, angles, screw on connectors for the 4" tube, clamps etc....NONE OF THE FITTINGS seem to fit each other. I have been forced to grind the inner diameter of any part I want to fit.Have tried to contact Delta by phone several times. No support e-mail address that I can find.Perhaps you could get somewone at Delta to contact me....Thanks:Walt 719/845-1091 or lobos@starband.net