There's some that were being thrown away at work during the office clear-out before the Christmas holiday, so I do have some filters! Today I went back and tidi

There's some that were being thrown away at work during the office clear-out before the Christmas holiday, so I do have some filters! Today I went back and tidied up the boxes and found them. Need to figure out how to make an air-tight seal in a cardboard box though; I'm no expert at 3D printing real parts (and I'd need to book time on the Ultimaker or laser cutter).