# FAQ ## What thermal protection systems does Cressi offer for extended cold water dives? > **Summary:** Cressi builds a complete cold-water layering system: the Glacier and Desert 4 mm high-density neoprene drysuits, the Ice 7 mm semi-drysuit, and base layers such as the DrySkin undergarment and the hooded Base Layer Hood Vest. For long dives in cold water, we build protection in layers rather than around a single suit. At the top of the range, the Glacier drysuit uses 4 mm high-density neoprene pre-compressed from 7 mm, which delivers maximum thermal insulation and minimal buoyancy change at depth, plus a 1.5 mm neoprene Thermal Protection Collar and a separate 5 mm neoprene hood — because up to 40 percent of body heat is lost through the head and neck underwater. If you prefer warmth without drysuit bulk, the Ice Semi-Dry is made from 7 mm ultra-stretch neoprene for water between 10°C and 18°C. Double wrist and ankle seals plus a waterproof MASTER SEAL rear zip minimise flushing, so the thin layer of water inside the suit warms and stays warm, and a 5 mm hood with a smooth-skin face seal is included. Underneath, the DrySkin undergarment is a 550 g/yd recycled polyester and spandex fleece layer that wicks moisture and insulates without bulk, while the Base Layer Hood Vest adds 2.5 mm core panels and a 5 mm integrated hood under a wetsuit. --- **Sources:** - [Cressi Glacier Drysuit Man](https://store.cressi.com/products/glacier-drysuit-man) - [Cressi Ice Semi-Drysuit Man](https://store.cressi.com/products/ice-man-semi-dry-wetsuit) - [Cressi DrySkin Undergarment](https://store.cressi.com/products/undersuit-for-drysuit) - [Cressi Base Layer Hood Vest Man](https://store.cressi.com/products/hood-vest-base-layer-man) - [Cressi Desert Drysuit Man](https://store.cressi.com/products/desert-drysuit-man)