Rocboc Car Air Freshener Cup Holder Mount Air Purifier with HEPA, Negative Ion and Carbon Filter Rocboc Car Air Freshener Best for cars and SUVs within 3 cubic meters space. Its aluminum and magnesium alloy surface with tiny-stripes designs fits your car environment Builtin negative ion producer sterilizes and purifies the in car air. Zeolites and activated carbon used to adsorb hazardous gaseous phase of toluene, ammonia, and formaldehyde. It adsorbs up to 99.7 percent of smelly molecules and provides with cleaner air. Smart and intelligent Air purifier- With the built-in smart chip, pillar gauging the in car air condition when turned on. It automatically starts purifying when the air quality is bad to provide a safe and healthy air environment for every user.