Prusa i3 Mk3 Roller Spool Holder

This is Remix of the excellent universal spool roller unit & stand by DWONH. See the original thing for assembly diagram.
It uses 608zz bearings, no bolts and nuts are required to assemble.
Rollers are 120mm long which should be sufficient for most 1kg filament spools.

I was unhappy with the supplied spool holder on the new Original Prusa i3 Mk3 printer. Although a large improvement on the Mk2 version I still found it flimsy and would "bounce" the roll of filament producing movement in the