The Optimum 4000 represents the new standard in air treatment technology. Versatile, safe, and effective, this quiet, compact electric unit improves indoor air quality using Vaportek’s patented non-toxic membrane. The infinitely adjustable output control and simple cartridge replacement system makes the Optimum 4000 the choice for air-quality professionals. The Optimum 4000 neutralizes odors instead of masking them. The standard output cartridge will remain effective for up to 3 months. Measures 5" X 5" X 12" long.