[InFlight]

I have always found most filter storage options are a nuisance at best to use when backpacking.

Stack Caps are a method to thread your filters into each other, and are a matching pair of end protectors.  You can then safely keep your filters in a handy pocket safely,  rather then some wallet buried somewhere in your pack that you need to remove to access.

It’s simple enough to remove just the single filter as needed and re-stack.