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A DIY valve overdrive pedal – Goldie – Dave Mac's Window on the World
Pneumatic Foot Pedal Valve 1/4-inch Air Inlet & Outlet 1/8-inch Exhaust 3 Way 2 Position Pneumatic Air Control Foot Press Valve Direct Drive Type - Walmart.com
1/4" NPT Pneumatic Foot Pedal Valves 2 Position 3 Way