0.375 to 0.02″ Expansion Diam, 950 Lb Holding Force, 8-32 Mounting Screw, Stainless Steel ID Expansion Clamp 3/8″ Flange Diam, 3/8″ Flange Thickness, 3/8″ Mount Hole Diam, 1 Mount Hole, 3/4″ Overall Height