Review on 🔴 Kuman CNC Shield Expansion Board V3.0 + Uno R3 Board + A4988 Stepper Motor Driver with Heatsink for Arduino Kits K75 (CNC Shield + Uno R3 + Stepper Motor) (K75-CNC-UK), Red Blue by Nathan Byard

In short, this is a decent kit. The stepper motor controls aren't outstanding, but they work and the system is generally pin-compatible with GRBL. However, the reason it loses two stars is that the kit is incomplete. At the time of writing, the kit does not include the jumpers needed to set the microstepping modes under each stepper motor module. These are contacts "M1", "M2" and "M3". The end result is that if you don't connect to geared steppers, you lose resolution on the move (i.e. you get stuck at a full step instead of the near-standard 16x microstepping). That means adding another $6-10 to buy jumpers or solder the step mode pins.