Supports the following standards: ASTM D6926, AASHTO T245 4" compaction mold assembly for preparing test specimens with H-1336 mechanical compactors and H-1340 and H-1345 hand compactors. Mold is machined from seamless tubing and plated. Mold is comprised of a base plate, mold cylinder and extension collar. Base plate and collar are interchangeable with either end of the forming mold. Forming mold is 4" (102mm) ID by 3" (76mm) high.