MIDI Controller 4 Buttons Footswitch support USB MIDI Foot | eBay
Compact Amperos Control 4 Buttons Footswitch Support Standard Usb Bluetooth Midi Foot Controller Volume Expression 2 In1 Pedal - Guitar Parts & Accessories - AliExpress
Footswitch MIDI | MIDI USB Pedal Controller
GitHub - SteveObert/KatanaUSB_Midi_controller: This is a Teensy based USB MIDI foot controller for Katana amps
Best MIDI Foot Controllers for Guitar - Guitar Gear Finder