The Blueair 203 'Slim' is an update on the classic 203 version. 'Slim' now has an even thinner, and delicately redesigned body profile. This new model effectively removes every type of particulate air pollutants, including PM2.5, allergens, pollen, mold spores, dust, pet dander, bacteria, and viruses. Blueair units purify more air, more quietly, using less electricity than any other brand.