Light shelf based on 9x9mm square pipe

This is a light shelf based on 9x9mm aluminum square pipe. All you need is a printer and some 9x9 pipes. 

To secure the shelves, holes for M3 bolts and nuts are built in in the three-way connector. The holes for 9x9 pipe are made bigger and adjusted for my printer, so one might want to adjust the size of the holes if they are too tight or too loose. 

I built a 1m shelf, which is stackable. 2m high slim light shelf should be no problem. 

I printed in ABS, since my Voron handles it better then PLA, also ABS seems to be a better choice for continuous loads. However PLA should work fine, especially if you don't plan to load the shelve too much.

Used 0.6 nozzle and 0.3 layer height, 4 walls for extra strength. The parts are bulky to have some leeway in strength. My shelves can handle about 10 kg, though I wouldn't put too much on it, especially on the upper ones. Still, seems to hold without a problem.

Leg covers are printed in TPU.