This filament spool holder allows to keep your filament clean and dry. The box contains a light bulb, which dries the air and makes sure your filament is ready for printing. You can put up to 6 spools inside the holder and they can be different sizes. The box has a hole, through which you lead your filament to the printer, other than that, it is completely portable and easy to carry. I also installed a fan, which helps the air to circulate around the box, making it evenly warm. In the bottom of the box, I put some silica gel, which binds water and makes sure the air is dry.Needed parts: -a box -light bulb holder -aluminium sticks holder -2 aluminium sticks -a fan -2 light bulbs I bought the box from a local hardware store for 10 euros. Then I designed and printed the needed parts - a light bulb holder, and edge parts for the holder of spools, which you can see on the photos.I used two aluminium pipes, which hold the filaments.To achieve dying inside the box, I got two light bulbs. Because I didn't want overheating in certain parts, I installed a fan i got from a PC.