- 3mm insulating neoprene - Adjustable chin strap - Reflective strips on both sides - High-visibility central stripe - Smooth skin neoprene sides for improved performance - Comfortable fit Extend your swimming season with the Swim Secure Neoprene Swim Cap. The 3mm neoprene provides a warm insulating layer to reduce heat loss from your head and keep you comfortable in cooler water. The adjustable velcro chin strap and three different sizes mean you'll find the right fit for you. The high visibility central orange panel ensures you'll be seen by other water users, while the smooth skin neoprene side panels keep drag to a minimum. The cap is made from three panels of neoprene for a snug fit, and the seams are reinforced to ensure great performance in even the most challenging conditions. Reflective strips on both sides are ideal for low-light conditions. Size Head Circumference Inches / cm Small 19" - 21" / 49cm- 54cm Medium 21" - 23" / 54cm - 58cm Large 23" - 25" / 58cm - 63cm