Is missing beater and memory hub. AN INDUSTRY STANDARD GETS EVEN BETTER. Featuring a host of refinements and upgrades, the. Legendary line of 5000 Series bass drum. Pedals still features a choice of drive systems. Aluminum hex shafts, pedal plates and linkages. 101 two-way beater, and built in spurs. These pedals can be customized to fit the needs. The TURBOT (TD4) concentric drive system maintains a. Direct relationship between the sprocket and the footboard. To provide a solid, powerful, consistent feel and response.