Delivering high traction and a lightweight feel, the New Balance 1601 v2 is a performance-driven racing flat designed to propel you to the finish line. Fantom Fit skeletally engineered upper for ultralight support and fit. Created by fusing two extremely thin materials with a no-sew process. REVlite RC, a higher density version of REVlite foam that's engineered for greater responsiveness. Blown rubber. Wt. 5.5 oz.