Brocraft Clamp-On Rod Holder Silver Aluminum Horizontal Mount Fits 1-2in Pipe. These clamp-on rod holders are made from marine-grade T6 aluminum with a polished anodized silver finish. They clamp around pipes from 1 inch to 2 inches in outer diameter, making them ideal for boat T-tops, railings, or towers. The heavy-duty white vinyl lining protects your rods while the stainless steel bolts ensure even clamping pressure. Simply loosen and reposition the holders if you want to change their location. 6.7 x 6.2 x 10.6 inches.