Copper 3d's "solidrim" face mask fits my face pretty good, but the version you can download at opensourcemask.com (or https://copper3d.com/stl/g_facemask_nanohack.zip) comes without a logo (or other pattern to increase airflow). Good thing the CC BY-NC 4.0 license allows remixes! As Lost World Order are about to play their last concert in december (see https://metalconspiracy.de/ for more info on that), their old logo (from "This Apparatus Must Be Earthed!") has the right shape and "Endzeit Thrash Metal" goes well with face masks anyway, I extracted that via Inkscape and stamped it. Furthermore I wanted to use the headstrap from some old ski goggles, so I altered the fixture for that. Copper 3D stuff for this specific version is included, but I left out the version with separate rim here. Read their explanations - I reject any responsibility for health issues. This is NOT personal protective equipment (PPE).