This wall mount filament holder is designed to use as little material as possible. The print takes less than 30 minutes and uses 4 grams of material. It contains filament clips for 1,75 and 2,85mm filament which is able to hold the filament and let it loose if the spool is removed from the holder. The maximum edge width of the spool is 7mm and it is designed for 200mm spools but it should hold different diameters just fine. Mounting instructions can be found on the drawing. This thing can be downloaded from Thingiverse!