Simple and minimalistic spool core for your overture-spool, so your printer doesn't have to use that muche force. It got a perfect snug fit, so it can't fall of by itself. 

I printed mine from some leftover petg, but I guess pla will work just fine.

It takes a little bit of force to get it throw the second side, just insert it till it hits the backside and flip the spool around, place it on the floor and gently push it throw.