This is the Sharkskin Men&';s Climate Control Long Sleeve Shirt Exposure Garment for Scuba Diving, Surfing, etc. Features: This top is made from Chillproof material with an inbuilt radiator function It provides the ultimate versatility by being able to zip up for 100% warmth and protection Zip down when the sun comes out or your work rate goes up It also has a high collar to keep your neck warm Sharkskin Climate Control has all the same features as the Chillproof garments with the added benefit of the addition of a heavy-duty zipper. This allows you to control the amount of heat you keep in by adjusting the zipper to suit the conditions. PERFORMANCE GUARANTEE Authentic Sharkskin garments come with a 12 month guarantee on workmanship. Excludes fading and degeneration as a result of excessive exposure to chlorine or sunlight. We guarantee Sharkskin will perform as advertised.