Spool holder/roller for extreme light rolling to be mounted onto a 12mmx12mm wooden bar. Spool rolls with nearly no effort For spools with inner diameter of 50 mm or more. Note: might unroll the reminder of your spool, if too easy going, insert foam sponge into spool hole, size/fit of foam peace regulates the resistance 2 peaces each require (2x holder, 2x pin) mount the higher tips outside of the spool, which will hold the spool in place in place print instructions: 40% filling, 8 0.2mm top/bottom layers , 4 wall 0.5 mm external 1 Bearings 608 required tight fit onto wood bar, some filing might be required Pin has a hole, if too loose, use bent paperclip