Clamp fits 1u0026#34; to 1-1/4u0026#34; square railnMade from 304 Stainless Steel tube lined with a UV resistant black PVC and fitted with a chrome zinc alloy adjustable clampnAngle around rail is infinitely adjustablen9u0026#34; Tall Tube with 1-5/8u0026#34; IDnIncludes 304 Stainless mounting screws and the hex key needed to make angle adjustments and to tighten the clamp in placenCE Smith Pontoon Square Rail Adjustable Clamp-On Rod Holder, 55108A. Comes with 2 protective liners, one to fit 1" and one to fit 1-1/4" square rail. The liners are round on the outside allowing the rod holder to be adjusted to any angle above the water, and the hidden left or right adjustment allows even more adjustment choices ((in 15 degree increments). Plastic insulator sleeves are included to help provide snug fit on the rail. Gimbal pin keeps your rod from spinning. Solid bottom with drain holes prevents water from pooling.