Riser Clamp Bolt Diameter 1/2 in Bolt Length 1 1/2 in Clamp Material Steel Clamp Material Finish Copper-Plated For Copper Tube Size 4 in For Maximum Outside Diameter 4 1/8 in Load Capacity 300 lb Mounting Hole Diameter 0.438 in Overall Height 1.25 in Overall Length 2 in Overall Width 1 1/4 in For Use On Tube Standards MSS SP-58 Type 8 WW-H-171 Type 8