Use a 2-core cable to wire up our regular microswitches

IMPORTANT WARNING: Note: Incorrect wiring can short V+ to GND causing damage to your controller: Double check wiring before powering on. We recommend using 2-core wiring only for this type of switch to avoid accidentally shorting V+. Only connect SIG and GND pins on the BlackBox.

Make sure to set $5=7 to use Normally Open switches with grblHAL on the BlackBox X32

If you need a more EMI proof solution, consider upgrading to OpenBuilds Xtension Limit Switches

Micro Limit Switches

Lever Micro Limit Switches