This is an adjustable modular shelf. You need to ensure that you have a clean bed and you may have to turn off the aux fan to ensure parts dont warp. PETG is preferred but the pictures in the model are in PLA as a proof of concept and have functioned fine. You may potentially chip a piece of the snap connection off with PLA, so be careful.

This is a very tight fit to ensure the shelf doesn't fall off. I recommend printing the shelf first, then the sample piece. If the sample piece snaps in fine, print whatever size posts you want. If its too tight, adjust it to 98% or 99% scale to slightly make it smaller.