Supports the following standards: AASHTO T22, AASHTO T23, AASHTO T126, AASHTO T231 These heavy-duty vertical cylinder cappers are used in applying capping compound to concrete test cylinders in preparation for compression tests. The base and capping plate are machined from cold-rolled steel and the capping plate is finish-ground within .002" (.05mm) planeness. The cylinder guide is a rigid, one-piece standard, which is machined from high-strength, cast-aluminum alloy.