On Oct 20, 3:47*pm, "Stormin Mormon"
wrote:
I considered bungee cord, but figured it would leak air at
the place where the ends fasten. The paper filter goes over
the green foam.

Use a long bungee and wrap it around twice...

Hit the local office supply store for a bag of those big red rubber
bands and use several...

Buy a few feet of elastic at a fabric store...