Micro campus board holds V3 for climbing finger strength training, packaged in bulk.

The easiest one is 15mm deep, then 12mm and hardest 10mm. It's not easy, but was never meant to be :D Warm up before trying and make sure to 3d print it with high infill and multiple wall thickness like 40% 4walls minimum.

Check out the rest of my versions, where i changed the shape of the edge and optimised the size for 3D printing.