We got a new K400+ since they were on sale and my wife wanted to put it on the wall where the toddler couldn't reach it. I couldn't find a vertical wall mount holder I liked, so I made my own. She likes hexagons, so I gave it that flare.

Prints clean without supports. Recessed holes will take #6 or #8 screws (pictured with both drywall screws and anchor screws). All corners rounded out. Keyboard will fit either way with keys out, but not with keys towards the wall.

Two versions available - one with cutouts ("hollow" has bridges) and one with a solid backing (no bridges). The solid version could be used with adhesive backing if you do not want to use screws or anchors.

3MF built with STEP files (included) so it prints smoothly. Walls sized for uniform 0.42mm dimensions (as set in my profile)