It's always summer on the inside. Keep your core warm and stay lit!
That crazy looking pattern in the back of the jacket is O’Neill Firewall Magma. That’s a thermal energy-absorbing pattern that absorbs and retains significantly more body warmth than a conventional lining (like...25% more). It’s printed there because the back of the jacket is THE place to keep your core warm. It is breathable and moisture wicking too. Clever, huh? Jack O’Neill discovered years ago that it’s crucial to keep your core warm when he was developing wetsuits, and this latest technology is the next level of warmth efficiency in outerwear.