This thing is an adapter for the spool holder on a Trilab DeltiQ2 printer.
It might also fit with other printers from Trilab ( I don't know...).
You can reuse the parts from the original Trilab spool holder.
It lets you turn the filament spool 90° which IMHO makes more sense by putting less stress both on the filament and the extruder.
Two versions are available.
The "easy print" version is lighter, uses only 2 bolts, and doesn't need support.
The other one uses 3 bolts and can also be printed without support but it's a bit more difficult.
Anar
