SIZE CHART: S: Length: 16CM, barrel height: 15CM M: Length: 18CM, barrel height: 17CM L: Length: 20CM, barrel height: 19CM XL: Length: 22CM, barrel height: 21CM 2XL: length: 24CM, barrel height: 23CM 3XL: length: 26CM, barrel height: 25CM 4XL: length: 28CM, barrel height: 27CM MULTI-SPORT NEOPRENE DIVING SOCKS --- The neoprene diving socks are designed for universal usage for both ladies and men. Perfect for a variety of sports like beach/swimming/diving/surfing/snorkeling/kiteboarding and many others. DIFFERENT FROM OTHER DIVING SOCKS --- 1. The adjustable strap can make the welt cover your ankle tightly, prevent sands or other small things coming in. 2. With anti-slip design on sole and warm thermal materials, they protect your feet from hurt by rocks or other sharp objects and keep your feet warm underwater. Sandproof & Waterproof --- The swimming sock sole and outer front are made of wearable and heavy-duty fabric. Even when you walk on rough surfaces occasionally such as rocks and gravel, there is no damage to them which would be on normal neoprene socks. Besides, the top part of socks made of high-quality material snugly seals your feet and the neoprene was glued together by glue and blind stitched seam, which can prevent micro sand from getting into the socks. SKIN-FRIENDLY --- The diving socks are made by high-quality 3mm neoprene premium water socks with anti-slipping rubber soles, which is healthy, elastic, and durable. It can last for long even with frequent usage and protect your feet from cut, puncture, scratch, and cold water.