PF stands for Posture Foundation. Developed in 1933, this patented insole technology set a new standard in sneaker comfort. The insole technology was first used in BF Goodrich shoes. It involves a wedge-like insert (promoted as the “magic wedge”) that moves weight to the outside of the foot, evenly distributing weight, reducing leg strain. As the success of the sneakers with the Posture Foundation insole technology grew in 1937 it became the basis for the brand name, “PF Flyers.” In the 1930s and early 1940s PF Flyers was making sneakers, as well as oxfords, boots and heels. Sport styles by PF were very popular in the 1950s, renowned for helping you “run faster and jump higher” courtesy of the “action wedge.” This ability would be a result of the improved fit of the foundation, but similar foundations were finding their way into competing brands, countering the PF advantage.