Refresh your ThermApparel CoolSleeves with a new set of cooling packs.

These lightweight CoolSleeve66 cooling packs sit directly over the radial artery at your wrist and forearm. T

Think of it like a heat exchanger: the packs pull heat out of the blood flowing through the artery, and your body circulates that cooled blood back through your entire system, bringing your core temperature down from the inside out and cooling you head to toe.

They freeze safely above skin temperature, recharge fast, and deliver dry, comfortable cooling in both dry and humid heat.

This package includes:

• 2 CoolSleeve66 Cooling Packs

Key Features

• Replacement cooling packs for ThermApparel CoolSleeves
• Freezes around 66-70°F (19-21°C) for safe, comfortable skin contact (not ice-cold)
• Each pack is approximately 7" x 2.5" for a slim, low-bulk fit in the sleeve pocket
• Works in both humid and dry heat for reliable cooling outdoors or on the job
• Fast recharge: about 15 minutes in ice water, 45 minutes in the fridge, or 60 minutes in the freezer
• Non-toxic, bio-based PCM that is biodegradable and reusable thousands of times

Learn more about how our cooling packs work in our cooling pack guide.