A Solder Spool Holder for my 3 common solder sizes I use  0.6mm , 0.8mm & 1.0mm. Keeps the dust off and stops it unwanted spills. Also got all my solder in one spot. Requires an M4 Nut and an M4x20 Screw to bolt together. Front over can be glued on or snaps on. Recommend glueing case to shaft base.