28mm water filter adapter

Screw your water filter directly into any 28mm bottle neck with this adapter - tested with the Sawyer Squeeze but should fit any filter with a similar coke-bottle-style thread. I've modelled in a vent to allow air to escape as you're squeezing water into the clean-water bottle, so no need to pause to allow things to equalise. This vent hole is sloped downward to prevent any dirty water from finding a path in, just make sure the arrow on the adapter points in the direction of flow (it can be used in the opposite direction though if you're not fussy or if you like a twist of giardia in your water). There are two versions of the stl / 3mf - one with modelled support, and one with generated tree support. Both should work so just choose your favourite flavour.