Not my first choice, but the Coghlans version is still available, even in little stores in very out of the way places. It's the two-step set, so no need for iced tea crystals. I was waxing nostalgic, sort of.

Why would that matter? Well, I've seen a few situations where the ability to augment my mini-kit would be worthwhile. This includes work situations where a field office job morphs into remote site visits without warning. Fortunately the chlorine tabs are also increasingly available.