Pulled off my P1SC 1999 mustang GT The Procharger 4.13" 8-Rib Zero Offset Pulley is a high-quality pulley designed specifically for ProCharger superchargers. Made in the United States, this pulley features a zero offset design for improved efficiency and performance. It is a direct replacement for the OE/OEM Procharger 8-Rib pulley, ensuring a perfect fit and compatibility with your vehicle. Upgrade your car or truck with this durable and reliable pulley from ProCharger to enhance your air and fuel delivery system.