The Impacto Sorbo-Air insole is made of sorbothane, is packaged 16 pair per case and comes in blue/yellow. Proper sizing is important when buying this product. The size for this product is 11 to 12. These types of parts are designed for specific applications which feature ways of safeguarding & shielding itself and/or the user. This part is designed and manufactured such that it offers the following protection: Shock Absorption.