This vest is designed to be used with or without a wetsuit over it. In temperate waters, it can be used as an outer layer, protecting you from the cold and the sun without any restriction thanks to its sleeveless cut. In colder temperatures, it is the ideal accessory to wear underneath your wetsuit while swimming in open water. Materials: This vest is made with 2 mm thick neoprene and an SCS coating. › See more product details