Stash Tea
Specs partially disclosed stashtea.com ↗
Not marketed as a plastic-free brand, but the bag is: Stash's filter paper is 100% cellulose (wood) fiber, machine-folded and pressed so no glue is needed or used, with a cotton string, a paper tag, and a metal staple (not plastic) as the only non-compostable part. The company confirms the paper is not chlorine-bleached and states the bags contain no plastic.
How clear are their specs?
FAQ confirms the 100% cellulose bag, the glue-free fold-and-press seal, and the absence of chlorine dioxide and plastic - but doesn't detail per-line variation or publish independent testing.