An air conditioner is nothing but a sum of its parts, with Air System Components (ASC) supplying the parts. The company manufactures components, such as grilles, registers, diffusers, and terminals for air conditioning, heating and ventilation systems, in addition to other air distribution products. ASC's products are used in industrial facilities, institutions, and commercial and residential buildings. Brands, which operate as independent companies, include Titus, Krueger, Tuttle & Bailey, Superior Rex, and PennBarry. Its Trion Indoor Air Quality arm focuses on air filtration supplies. Products are available through wholesalers and distributors. ASC, which has about 10 plants, is a subsidiary of Tomkins.