Medical-grade silicone body. 316L stainless collar. Threads onto any standard 42mm filter — Katadyn, Sawyer, LifeStraw. Every production batch will be lab-tested for leaching. I'm documenting the build from sourcing to shipping.
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I'm a 23-year-old CPA based in Northern California. I love trail running. A couple of years ago I started reading about what's actually in the gear I run with — the soft flasks, the bladders, the bite valves — and I couldn't unsee it.
Every soft flask on the market is thermoplastic polyurethane. Under sunlight and heat, TPU photo-oxidizes. It leaches VOCs and microplastics into your water. The "plastic taste" everyone complains about isn't in your head — it's the sensory signal of what's already in your bottle.
So I cap my regular runs at two hours. About ten miles. I'd rather run four-hour days in the Sierras, but I don't want to drink from a TPU flask, and stainless bottles don't fit in a vest or thread onto a filter. The category forced a tradeoff I refuse to accept.
PurePath is what I'm building because no one else has. It's not vaporware — I'll show you the supplier emails, the rejected prototypes, the lab reports, the failures. If you want one, get on the list. If you just want to watch, that works too.
USP Class VI platinum-cured silicone body. 316L surgical stainless collar. 100% silicone bite valve and gasket. No TPU, no PE, no painted logos, no plastic threads.
Threads onto every major trail filter — Katadyn BeFree, Sawyer Squeeze, LifeStraw Peak. No proprietary lock-in. Use the gear you already trust.
Third-party GC-MS testing planned for samples from every production run. Results will be published publicly, not buried. The certificate of purity should be real, not marketing copy.