Simple shelf bracket

Dimensions: 100x100x20 [mm]

                             75x75x15 [mm]

                             50x50x10  [mm]

Test print 100x100x20 [mm] with PLA, 1 mm wall thickness, 50% infill, holds 10 kg load safely (that's for a pair of brackets).

Didn't test the load limit jet but for heavier loads use 100% infill or stronger material like ABS, PETG...