Keeping your head warm, so you can swim longer, the Gul Petrel 7 Seas Swim Cap is ready to make a splash in the open water. Thicker than your regular swimming cap, and featuring Revofit 3D-moulded technology for optimum fit and comfort, it gives outstanding hydrodynamic performance to help reduce heat loss from your head. Team it up with the Gul Neoprene Swim Cap and you\\\'re well wrapped up for facing the cold British waters all year round. Key features white colour option features \\\'Firefly\\\' Technology which allows the cap to glow in low light conditions - a great safety feature for open water swimming available in black and white colours easy to use, comfy and streamlined to deliver you ultimate performance. 100% 3D silicone can be worn under the Gul Neoprene Skull Cap for added warmth