Chemex
Plastic-free almost by accident: the design was finished in 1941 and never needed updating, so it's still borosilicate glass with a wood collar and leather tie. Chemex doesn't market "plastic-free" — they don't have to. The only caveat is the paper filters (a wood-pulp product, not plastic) and, if you buy the glass-handle version, there's no polymer anywhere in the brew path.
How clear are their specs?
Not much to disclose — it's glass, wood, and leather, visibly so. No coatings, no hidden liners, no proprietary materials to interrogate.
Products we recommend
Products to avoid
Documented so you know what to skip — each still has a full breakdown and sources.