The most advanced antibacterial PP spun cartridge on the market. UST-M is currently the only company on the world which uses this advanced technology in water treatment. To provide a totally safe antimicrobial protection, FDA GRAS (Generally Recognized As Safe) approved substance was utilized. In contrast with competitive products it does NOT contain nano-size materials and any other chemical additives, which may cause adverse effect on human health (inflammatory response, rash, etc.) This cartridge has a gradient structure where fiber density increases towards the interior. Such multiple structure improves filtration quality. The process was additionally improved by UST-M engineers, what additionally increased cartridge longevity. Due to the highest quality, this cartridge is able to remove sediments such as sand silt, rust and suspended solids down to 1 micron.