Onyx Cool Phase-Change Cooling Gear

How Onyx Cool Works

Onyx Cool is built around phase-change material, which is the key to its comfort: instead of the harsh, brief chill of ice, PCM packs absorb body heat and hold a fixed, comfortable temperature for a long stretch before needing to recharge. That's why the packs come in 58F and 80F versions, letting you choose a deeper cool or a gentler, longer-lasting one. The modular design, targeting the head, knee, shoulder, back, and hip, means you cool exactly the spot that runs hot rather than chilling your whole body.

Choose your temperature

The 58F packs deliver a cooler, more intense effect, while the 80F versions give a milder, longer-lasting cool that some find more comfortable for all-day wear. Pick by how much cooling you want.

Target the hot spot

The cap inserts, knee, shoulder, and back/hip pads let you place cooling exactly where you overheat, unlike a full vest. It's a flexible, modular approach to staying cool.

Vests and more cooling

The 80-degree Safety Pro Vest brings PCM cooling to the whole torso for work in the heat. Compare with our phase change cooling vests and cooling vests collections.

Shop related collections: Phase Change Cooling Vests | Cooling Vests | Cooling Hats