Steel Retainers are used for compressive strength testing of concrete cylinders. The retainers are made of alloy steel, precisely machined to specified dimensions, and plated inside and out to resist corrosion. All bearing surfaces are plane to within 0.002in (0.05mm). The Retainers meet ASTM C1231 and AASHTO T 22 requirements and do not require acceptance testing.
A steel retainer ring holds Neoprene Pads in place at each end of the concrete cylinder specimen. Retainers last for several years with proper care. Steel Retainers are sold in sets of two and available for 6in, 4in, 3in, or 2in diameter concrete cylinders.