Hang two filament spools on your Anet ET4/ET5. You can provide filament to the 3D printer from either spools. Print extender.stl and futa_11_1.stl in x,y 106% and z 100%. Requirements: Paper tube: ID = 23.3 mm, OD = 27.3 mm, L = 88.0 mm, from 50 m Saran Wrap package in Japan Inner attachement: extender.stl End cap: futa_11_1.stl Countersunk screw: M6x80 Glue: insert the attachement into the paper tube Paper washer: with a hole of diameter 29 mm Print extender.stl and futa_11_1.stl in x,y 106% and z 100%. Inner attachment with D20x1.5mm pitch screw thread and M6x1mm pitch screw thread (Tube shape support is already attached.) MD5 (extender.FCStd) = f11b654a8180d0b3da2664927b742813 (FreeCAD source) MD5 (extender.stl) = c29f66cf48abe93917826fecb18add9f End cap MD5 (futa_11_1.FCStd) = efff9a597e153c05ecd5301ffa2e9b05 (FreeCAD source) MD5 (futa_11_1.stl) = 86f9a3775264d713a65951fd878f1248