These are awesome! I use them to vacuum seal up my PLA 3D printing filament spools to prevent them from becoming brittle from humidity damage. At any one time I’m storing about 15 x 1kg spools and this pack of vacuum bags caters for that easily with bags to spare. So quick and easy to pack and seal, and unseal/reseal ever time I change spool colours. I can use my studio DeWalt mini vacuum to seal, or our big household Miele - works perfectly with either.