Expansion Plug, Thumb Nut, 5/16 In Price For: Each For Use In: Low pressure seal in circular openings Max. Back Pressure: 24 ft. of Head Material: Aluminum, Stainless Steel, Neoprene Rubber Item: Mechanical Expansion Plug Type: Thumb Nut Min. Dia.: 0.297" Max. Diameter: 0.3375" Nominal Size: 5/16" Country of Origin (subject to change): United States