Your palms contain specialized blood vessel structures (AVAs) that act as your body's natural radiators, allowing large volumes of blood to release heat near the skin's surface. By holding a cool — not cold — surface against your palms, you accelerate the offloading of core body heat. The Narwhals are engineered to hit the precise temperature range where this process is most effective.

If the surface is too cold (below ~50°F), your blood vessels constrict and blood flow stops — which actually shuts down the heat-transfer process. The Narwhals' Cool-Not-Cold® packs keep the device in the 50–60°F therapeutic range, where heat exchange is maximized without triggering vasoconstriction.

The Narwhals are versatile. Use them for 3–5 minutes before a race or hard effort as a pre-cooling strategy, between sets or during timeouts for inter-effort recovery, or as part of a post-training wind-down routine. Many athletes also use them to help lower arousal before sleep after late evening sessions.

The Narwhals maintain effective cooling for 2+ hours of use, even in warm conditions. Each set comes with four Cool-Not-Cold® packs so you always have a frozen set ready while the other is in use.

Freeze the Cool-Not-Cold® packs overnight. When you're ready to use them, place the packs inside the Narwhals and fill with approximately 75°F (room temperature) water to the fill line. Total setup time is about 60 seconds, and they can be prepped hours in advance.