The jazz 18 comes fully equipped there is heel progrid for premium cushioning underfoot with a medial support arc that adds extra support the midfoot weld on the upper provides lightweight support to keep your foot comfortable throughout your run upper tpu lateral weld for stability hydramax collar lining collar lining material combines superior moisture wicking properties with a plush feel for comfort comfortlite sockliner moulded sockliner contoured to cradle the heel support the ar