ESP32 dev board storage rack with 10 slots
A desk rack that stores ESP32 DevKit, ESP32-C3, ESP8266 NodeMCU and Arduino Nano boards upright with their USB ports facing up so the right one is easy to grab. Typical 30-pin ESP32 DevKit boards are 55 x 28 mm with header pins protruding 6 mm below, so each of the ten slots is 30 mm wide and 12 mm deep with a 3.5 mm channel that swallows the pins and a 0.5 mm clearance for the PCB; slot pitch is 18 mm to clear USB shields. The base is 190 x 45 x 20 mm with 2 mm walls and a 1 mm embossed number beside each slot. Prints upright with no supports.
A rack made for your actual board mix stops the drawer-of-loose-boards problem better than a download that assumes one size. In SpeakCAD you describe the boards, preview the rack free in the browser, add wider slots for a Wemos D1 Mini or an Uno in the chat, and download the STL.
Design a dev board storage rack 190 x 45 x 20 mm with 2 mm walls and ten slots 30 mm wide and 12 mm deep at 18 mm pitch for ESP32 DevKit boards 55 x 28 mm, each slot with a 3.5 mm pin header channel, 0.5 mm PCB clearance and a 1 mm embossed slot number.