Neatly guide the filament into the printer to increase the dependability of the machine. the only outside hardware required is the standard roller skate 608 bearing with whatever suffix of your choosing, some super glue to secure the pulley around the bearing once inserted and a longer bowden tube (needs to be about 2 inches longer than stock. This has been designed for PETG, A nice slippery material. I recommend darker colors as bright PETG doesn't take as well to cyanoacrylate (super) glue. I imagine a bearing really isn't needed, you could make your own pulley for the spindle, but i like to over engineer things. For Print setting I recommend top and bottom at 1.4 mm (7 layers) , side walls at 5 layers and 15% or more gyroid infill. this device is strong enough to pick up a full spool of filament, in the drier and pull the bowden tube into the pulley without noticing. When installing the device the screws only need be snug plus. The bowden Tube only need stick out of the end of its place of security about an inch or less. the filament is always going to wobble around a bit to it's good the tube stick out enough to flexible. the filament extender should be away enough from the printer so the tube gracefully curves, you'll know it's graceful if you can push the filament smoothly into the printer.