Combine with a IKEA samla box and you have your own drybox that fits 4x 1kg spools.

See IKEA box here: https://www.ikea.com/se/en/p/samla-box-with-lid-transparent-s69440822/#content

and you can use this tube: https://www.ikea.com/se/en/p/hultarp-rail-nickel-plated-90444432/

The files contain a silica gel box that also works as a filament holder. You have to add your own 16mm steel or allu tube.