Crease and Board Stiffness testing is useful to industries of corrugated, carton board, paper, printing and packaging. The relationship between board stiffness and crease recovery (spring back) is an important factor in the performance of cartons on high speed packaging machines and in manual folding. It is crucial to have the creases in boards correct and uniform. The crease recovery (spring back) can result in forces, which distort the carton or cause stresses to be applied to closures, which reduce their effectiveness.