Bracket to make a filament spool holder shelf.  

Use ¾" (19mm) metal conduit or wood dowels to create shelf to hold 8" (200mm) 1-kg spools.  Bracket also has three ½" (13mm) holes to accommodate smaller spools, like the 6" (150mm) 250g spools.

The upright has 2 countersunk screw/bolt mounting holes.