PDP Concept Series Double Chain Single Bass Drum Pedal. Designed for optimal playability, the Concept Series pedal is a boutique-inspired machine that’s quick and responsive. The single-post design is outfitted with a dual chain concentric drive system, smooth cast extended footboard with integrated needle bearing hinge, and an offset toe clamp. Low-mass cam Dual-chain drive DW-style spring rocker adjustment. Model Name (Old) : PDSPCO. Pedal Drive Type (Old) : Chain Drive. For Instrument (Old) : Drum Set.