Universal Adjustable Crankshaft Pulley Holding Tool.

Holds vibration damper when loosening and tightening center bolt.
One side of the U shaped head is on a sprung pivot meaning the head can spring in and out to suit any pulley size diameter or shape. 

Engines: 

• Mercedes: M137 / M112 / M113 / M271 / M642
• Nissan: A32 / A33
• Universal - Most 3 leg / 4 leg or any pulley that you can get two 16mm pins into.