Quantity   Component name
1 × Organ Pedalboard My son was lucky to get a used one for free from an organ builder company. You may be brave and decide to build one yourself, there are several build logs out there.
1 × Arduino Uno R3
1 × Custom Arduino MIDI Shield Eagle CAD files are in the Github repo
4 × CD4021BE Shift Registers
32 × 10K 1/4W Resistors
1 × 34 Pin (2x17) Shrouded Header Normal 2.54mm pitch header, 2 rows of 17 pins
1 × 34 Conductor 1.27mm Pitch Ribbon Cable
1 × 34 Pin (2x17) Connector Socket Normal 2.54mm pitch connector, 2 rows of 17 pins for 1.27mm pitch cable.
32 × Reed Switches NO
32 × Small Magnets