For the easy removal of most harmonic balancers and drive pulleys which are press-fitted onto the crank-shaft. They are made from drop-forged alloy steel. They are design to help prevent damage to the pulley and shaft. The sets also include a sturdy BMC case and a variety of adapters. The contents are : – 1 puller plate – 12 screws, each 3 pieces: 3/8NC16 X 57 MM – 3/8NC24 X 57 MM M6 X 1.0 X 60 MM – M8 X 1.25 X 60 MM – 1 center bolt 10 mm – 9 adaptors: M12 X 1.5 – 3/8NC16 M14 X 1.5 – 3/8NC16 M16 X 2.0 – 3/8NC16 1/2 X NC20 – 3/8NC16 9/16 X NC18 – 3/8NC16 7/16 X NC20 – 3/8NC16 3/4 X NC16 – 3/8NC16 5/8 X NC18 – 3/8NC16 3/8X NC16 – 3/8NC16 Genuine Neilsen Product