Reductor for spool inner hole. Will reduce any hole having 77mm-88mm to a fixed size of 55mm, perfect for AMS from Bambu Lab. I have bought a lot of PLA spools from various sources, each having different diameters for it's holes, most of them bigger than what was supported by my Bambu Lab A1 mini, so they ended up falling.
This will stay very well fixed on the support and after being used for a while, will allow the spools to glide easily enough when you need them, but still keep them firm when in operation.
The author marked this model as their own original creation.