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 of any player.The Turbo (TD4) concentric drive system maintains a direct relationship between the sprocket and the footboard to provide a solid, powerful, consistent feel and response.