Supports the following standards: ASTM D6023, ASTM C138, ASTM C29, AASHTO T19, AASHTO T121, AASHTO T158 Clear .625" (15.8mm) thick, acrylic plates used to strike off surface of unit weight measure samples. Use a plate that is 2" (50.8mm) larger than the diameter of the unit weight measure. NOTE: Use 2" larger plate than the diameter of the unit weight measure.