prinzler was astounded at the enormous and senseless loss of life that night. he sought a way for doors into public facilities to be locked from the outside, but to allow egress from the inside with minimal effort during an emergency. prinzler tapped into the architectural engineering abilities of henry h. dupont to develop a product. in 1908 the first model of a "panic bar" style egress device was released and vonnegut hardware company was utilized to market it. owing to the joint effort to develop and sell the product, it was sold under the name von duprin, a combination of the names vonnegut, dupont and prinzler.