Below is a list of Instrument Enclosures manufacturers from Norristown, Pennsylvania. Instrument enclosures protect electronic devices inside metal or plastic housing. Because of their sensitive circuitry, the components must be protected from dirt, water and accidental contact. Being kept in an enclosure prevents the intrusion of solid foreign objects as well as liquids to a certain extent. Instrument enclosures are made from aluminum, acrylonitrile butadiene styrene (ABS) plastic, stainless steel and, for certain models, polyester with fiberglass reinforcing.