Our take No one likes sweat pouring down his or her back, which is why everyone should like the Zyro. The pack barely touches your back: A butterfly-shaped pad cushions your shoulder blades, but the lower pack rests well off your back. “I sweated profusely on a 15-mile hike near Paulina Butte in Oregon in 85°F temps, but my back stayed relatively dry,” a tester reports. The foam shoulder pads have hundreds of honeycomb cutouts for even more ventilation. Tradeoff: Loads over 40 pounds caused slight pack sway.
The details An aluminum perimeter frame supports loads up to 50 pounds. The Zyro’s 42-inch-circumference maw is the biggest in test, good for bear canisters and big tents.
Trail cred “The shoulder yoke is super easy to adjust; it just slides up and down the frame,” one tester says.