UltraFlask™+ Filter Cap

I used to carry a heavy filter bottle on trail runs, but this cap threads right onto my existing flask and saves me a ton of weight. The filter works fast enough that I can drink straight from a stream without slowing down much.

First few runs with this filter cap and I’m impressed—the water flows fast enough that I don’t have to suck hard, but it still keeps grit out of my mouth.

Swapped this cap onto my 42mm flask before a trail half and didn't touch a single stream crossing the whole race. The threading is tight with zero drips, which I was honestly worried about. Filtering on the move feels effortless now.