The Agency Power CNC machined lightweight aluminum pulley is made from high grade 6061 material. Each pulley has the Agency Power text laser engraved. The pulley has been broached for a perfect fit and the redesigned lightweight center gives you the best possible advantage over the competition. The Agency Power pulley is the same diameter as the stock pulley. Keeping the diameter the same allows no issues to occur with the alternator as under driven pulleys sometimes cause. Weighing only 1.0lbs, it is almost 5lbs lighter then stock. This is also the lightest crank pulley on the market. This gives you quicker throttle response as well as more horsepower and torque. Saving on rotating mass results in better performance.