Thank you for viewing. 【Size】 XL 【Color】 Black 【Country of Origin】 USA 【Condition】 Used, Excellent This is an inner suit for drysuits made by OS Systems, which is also used by the US Coast Guard and the Japan Coast Guard. The lining is fleece. It is designed to release sweat to the outer fabric when you sweat inside. It is very warm and has excellent heat retention. OS Systems has an inner series that includes thin, all-season, and cold-weather types. This is the thickest type. Suitable for cold weather.