?"" thick premium Vinyl / Nitrile foam molecularly engineered to minimize compression set * ?"" thick premium Vinyl / Nitrile foam molecularly engineered to minimize compression set|Patented ""Keyhole"" design on side for superior flexibility with built-in wings for optimum knee protection|Provides superior protection when fielding and sliding|Nylon/Spandex fabric fits comfortably on back of leg for no restriction of movement|