Leather :Genuine leather cover provides a responsive, pro-style feel for the highest level of indoor competitionSpecialized V-tec:Specialized V-tec seams provide stronger manipulation for directional change advantages while playingOFFICIAL SIZE & WEIGHT: The size & weight used at the pro level, ideal for ages 13 and upINDOOR DURABILITY: Durable leather cover to last during intense indoor training along with maintaining consistent performance during indoor gameplayK1 PERFORMANCE: The K1 is designed to keep players from holding back, so that they can play to their potential with every touchHARNESSES KINETIC ENERGY: The internal command lining enables players to evoke more power and velocity through the transfer of kinetic energy, enabling stronger kills