The physiological response to cold stress is to reduce blood flow to the periphery and look after the body core, where it can often just be a matter of time before cold becomes the limiting factor in the safety and enjoyment of a dive. X-Core provides extreme thermal protection to the core, enabling longer, more comfortable dives.

Designed to be worn under an Arctic, Arctic Expedition, Halo 3D or any other drysuit undergarment, X-Core augments thermal protection to the extent that electric heating can be avoided in many instances. It performs best over a lightweight baselayer such as J2 or Xerotherm but the X-Core can also be worn as a next to skin garment for critical core protection.