Proof 72-Hour Merino Air T-Shirt
Engineered for peak performance, the all-new Proof 72-Hour Merino Air T-Shirt is the go-to upgrade for your most intense training sessions. Crafted from ultra-breathable merino mesh, it offers the same odor-resistance, moisture-wicking, and thermoregulating benefits as the original, but with even more stretch and a featherlight feel. The looser knit keeps things breezy during high-output efforts like hiking, biking, or HIIT, while the updated fit eliminates cling and maximizes comfort. Whether you are logging serious miles or just prefer staying cool on the move, this tee is designed to keep up, no matter how hard you push it.
