It has a 2mm neoprene upper for thermal insulation and an adjustable strap with hook-and-loop closure across the instep and around the heel for a secure, personalized fit. An EVA footbed provides additional insulation and protection. The bottom features a razor-siped Vibram® IdroGrip performance rubber outsole, which offers added slip resistance over a variety of surfaces. Please note that while it offers more slip resistance, Vibram® Idrogrip rubber is a marking compound.