Dual sided spool holder based on SeeMeCNC panels for dual extruder upgrades. Uses 1/4" threaded rod and 1/4x20 nuts because "'Murica" is a terrible place to source metric hardware. You can metric it up if you want. I print the panels at 100% honeycomb infill 3/top 3/bottom 2/outline concentric. The spool holders at 30% honeycomb. 60% of nozzle height. The nylock holders printed fine without supports. Print 5x nylock, 2x washer, 2x spool and one each of front back and middle. Assemble them like the pictures. If your rostock is assembled correctly vs the way it is in the V3 manual you will have to flip the dome and nyloc slot on the front panel. SeeMeCNC has worse technical writers than most 3rd grade classrooms so mine is flipped :)