PlanetCare
PlanetCare's filter is a plastic housing with a plastic-and-media cartridge - a mitigation device, not a plastic-free product. What sets it apart is the closed loop: cartridges go back to be cleaned and reused rather than landfilled, which addresses the "captured fiber has to go somewhere" problem better than most. Its own testing claims very high capture; independent mixed-load numbers have come in lower, so treat the headline figure as a manufacturer claim.
How clear are their specs?
Open about the cartridge system and closed loop, but its high capture figures are largely self-reported and run ahead of independent mixed-load testing.