Kamik Kids Womens Bluster 2 (Toddler/Little Kid/Big Kid) Neoprene Boot opening measures approximately 13" around Their Bluster is warranted in the comfortable boots from Kamik&reg; Kids! Lightweight and waterproof 7mm four-way stretch neoprene upper. Dual weather handles for easy pull-on construction. Waterproof and lightweight injected RubberHe shell. Antimicrobial footbed keeps feet fresh. Self cleaning, multi-season ZEUS RubberHe outsole. Temperature rated: -22&#176;F/-30&#176;C Made in the USA and Canada. Measurements: Heel Height: 1 in Weight: 1 lb 3 oz Circumference: 13 in Shaft: 9 1&frasl;2 in Product measurements were taken using size 2 Little Kid, width M. Please note that measurements may vary by size.