 Pratt was, in effect, DuPont's man on the inside, initially solely looking out for DuPont's interests.Pratt rose to become a member of the corporation's executive committee and, from the 1923 until 1968, served on GM's Board of Directors.He was later a company Vice President and is credited with supporting the idea of holding (as opposed to selling off) what became the Frigidaire Division of GM and encouraging the development of the coolant, Freon.