MechaTrellis is a custom remix of the popular Adafruit Neotrellis 4x4 keypad board - but re-designed for mechanical keyboard switches instead of rubber buttons.
A dual footprint lets you use either Cherry MX or Choc V1 switches.
As with NeoTrellis, each switch position has a full color RGB LED (NeoPixel compatible)
These 4x4 button boards
