lumen — Keychain Bottle Filter Cap
An ultra-compact, passive (non-motorized) keychain water filter cap concept designed for standard single-use plastic bottles. Features a Ø32 × 44 mm bead-blasted 6061-T6 aluminum outer shell with a continuous R2.0 mm top fillet, a recessed flip-top lid with a spring detent, a passivated 304 stainless steel and platinum-cured silicone internal water path, and a tool-free quarter-turn bayonet filter carrier.