Edelbrock 3.875in. pulley part #15847 allows you to fine tune the airflow and performance of your Edelbrock C7 Corvette or Enforcer Supercharger system to your preference. The Edelbrock #15847 features a 10-rib design for use with our Edelbrock street rod and muscle car Supercharger systems. Edelbrock pulley part #15847 offers a Black Anodized finish. - 3.875in. 10-Rib Edelbrock's/C Pulley in Black Finish for Enforcer Systems