*This tool allows for the easy adjustment
  or release of tension of the camshaft
  spur belts having idler pulleys with pin
  holes.
*In operation, this spanner wrench grips
  the center of the idler pulley and rotates
  it around its off-center retaining bolt.
*This rotation then allows for camshaft 
  spur belt tension adjustment .
*Made from heat treated alloy steel
  and a soft grip handle.