Pre-Owned Gear & B-Stock. PDP PDDPCO Concept Series Double Pedal. Designed in California by Drum Workshop for optimal playability, the Concept Series Double Pedal is a boutique-inspired machine that’s quick and responsive. The pedalâs design is outfitted with a dual chain concentric drive system, smooth cast extended footboard with integrated needle bearing hinge, single post auxiliary pedal, telescoping linkage with universal joints, and an offset toe clamp. Post Frame with adjustable spring rocker. Solid base plate with Magnetic Drum Key. Merchandise and packaging MUST be in the same condition as when received. Alto Music reserves the right to refuse any return if it appears the item has been used. Software (if unsealed or registered). Harmonicas, Mouthpieces, Earbuds/Earphones/Headphones(if unsealed), or any item that may come in contact with the mouth, ears or nose. There are no warranties for the following items.