METAL Our 1" fittings have an inner diameter of 1 1/4". Which works with 1" EMT pipe that has an outer diameter of 1 3/16". You can pick up the pipe at most hardware stores. Heavy Duty (Galvanized Steel) Fitting(s) with welded connections, nuts that are welded all the way around for strength and tightening eyebolts. If the nut weld does not go all the way around like in the picture please return to sender for a replacement 102 Degree angle These are used as the corner fittings for a low peak set up, Slant leg batting cage corners and also for the lower corners of a slant/lean to set up Heavy Duty Fitting(s) (Galvanized Steel) w/ tightening eyebolts, 1pc, Welded connections Our 1" fittings have an inner diameter of 1 1/4". Which works with 1" EMT pipe that has an outer diameter of 1 3/16". You can pick up the pipe at most hardware stores. These are used as the corner fittings for a low peak set up, Slant leg batting cage corners and also for the lower corners of a slant/lean to set up