PAX refers to a family of companies, including PAX Scientific, PAX Water, and PAX Mixer. The PAX companies are engineering research and development firms that employ unique, patented design geometries to improve fluid-handling equipment. PAX develops, licenses, and manufactures its technology to a variety of markets.

• PAX Scientific's focus is air-handling technologies such as fans and blowers, and marine hull design.
• A subsidiary of PAX Scientific, PAX Water Technologies commercializes technologies for water and wastewater management.
• PAX Mixer, also a subsidiary of PAX Scientific, markets industrial mixing technologies (other than water or wastewater mixers).

PAX is also associated with three master licensees that have "pax" in their name: PaxFan, PaxIT, and PaxAuto, sometimes collectively called PaxFan. These companies commercialize PAX Scientific's fan designs in the industrial, domestic, computer and automotive markets. PAX does not own nor operate the PaxFan companies.