A drysuit keeps you dry. What you wear underneath keeps you warm. This collection covers the complete Fourth Element thermal system for drysuit diving: baselayers, undergarments, socks, dry gloves and glove liners, built to work together so you can match your insulation to your water temperature and dive time.
Start with the baselayer
The layer against your skin manages moisture, and moisture is what makes divers cold inside a dry suit. The Fourth Element J2 Baselayer is a super-light wicking layer worn under any undergarment. It quickly wicks away perspiration without affecting your buoyancy, and its antibacterial fabric makes it the right choice for trips with several days of diving in a row.
The Fourth Element Xerotherm sits between baselayer and undergarment. Its fabric was originally developed for NASA and traps a layer of air next to the skin, adding warmth without bulk. Wear it directly on the skin in milder water, or over the J2 when it gets colder. It keeps performing when wet, to the point that some divers only notice a suit leak after the dive.
The insulating layer
The Fourth Element Arctic is the benchmark: the most versatile drysuit undergarment in the range, worn on its own or as part of a layering system in colder conditions. Its fast-wicking, high-insulation fabrics create a microclimate around you, and they retain much of their thermal performance even when wet.
The New Fourth Element Arctic X takes everything divers trust about the Arctic and refines it, with enhanced comfort, improved mobility, and everyday versatility. It is warm enough for cold-water diving and comfortable enough to wear on the surface between dives.
For the coldest water and the longest runtimes, the Fourth Element Halo A°R uses A°RGON aerogel insulation, a material developed for space exploration and cryogenics. The result is extreme thermal protection from a thinner, less buoyant undersuit, with body-mapped insulation optimized for horizontal trim.
As a guide from Fourth Element's own layering recommendations, the Arctic on its own covers roughly 7 to 14 °C, and combined with the Xerotherm, around 5 to 13 °C. Water temperature, dive time, and your own cold tolerance all shift these ranges, so when in doubt, ask us.
Feet and hands
Your extremities lose heat fastest. Cold hands cost you the dexterity you need for clips, valves, and camera work, and cold feet can end a dive before your bottom time does. Insulating socks complete the undergarment system inside your drysuit boots or socks. A dry glove system keeps your hands dry, while the liner worn inside provides the actual warmth. Liners come in different weights, so you adjust insulation to the conditions without changing the glove itself.
