RATTMMOTOR 3D Printer CNC Controller Kit Compatible with Arduino IDE, Nema17 Stepper Motor+UNO R3 Improvement Borad+CNC GRBL Shield Board V3 Expansion Board+DRV8825 Drivers+Mechanical Switches

Steppers all work. Drivers all work. Make sure you dial in the amperage with the screw on the driver for all of your steppers so you don't fry your driver chips; v20 on your multimeter and double the readout and that's the amps you're giving each driver. They're a bit finicky and in no way precise, and will definitely move over time.Modded some 28byj-48 to bipolar and they also run... fine... on this board... as fine as a $1 stepper will run anyway.Only complaint is that it's a bit expensive for what you're really getting. They're not TMC2209's.

Stepped motors works fine, but stepped drivers not reliable. You have to have use screwdriver to adjust for current flow, also they take current from each other.The bolts in the kit are not suitable for mounting the motors.

No work right out of the box. Got my investigation delayed.

Book cover had a rip.