Prefilter cartridges¶ Each entry records a named product and its sourced compatibility claims. Manufacturer claims remain unmeasured unless a project measurement is explicitly recorded. Missing fit links mean no supported claim is recorded here. Current entries¶ Viomi M1-PCB Filter Viomi Pure B6W PPC Filter Viomi V6/8 Pro-PCB Filter Viomi V6/8-PCB Filter Xiaomi A1-PPC-1A Xiaomi J21-PPC-1