Giving you 40% greater energy rebound, the unique BOOMERANG footbed is the ultimate cushioned insole for all sports shoes. As your foot strikes the ground our revolutionary foam structure retains more energy than ever before. Hundreds of expanded TPU beads compress and then spring back, releasing that energy to propel your forwards with increased speed and bounce. Meticulously designed and rigorously tested to retain its thickness and optimum performance level for far longer. The BOOMERANG insole fits most sports shoes, can be easily switched in and out of different pairs, and grips tightly underneath to ensure no slippage.