Holley's high-mount accessory drive has everything pulled up and in tighter than other options. The patent pending accessory drive incorporates the timing cover, water pump, and alternator and can also be configured with A/C and/or P/S if desired. This system works with the factory crank pulley, as well as aftermarket damper/pulleys. The accessory drive components in this system can be configured in several different ways. For example, there are alternator options available for different performance and electrical demands. Also, deleting the A/C and/or P/S are options if configured as a custom modular setup. The "base kits" supply all but the components with options. If you purchased a "Holley complete kit," all these options are already chosen for the most common, cost-effective combination. *This is replacement hardware for complete kit 20-310 or 20-310BK and optional A/C Bracket kit 97-403 or 97-421(black).