The men's Proton LT Jacket is an exceptionally lightweight insulator that delivers air permeability and warmth during high-alpine activities. It's padded with Coreloft Continuous 65 insulation and protected with a Fortius Air 40 outer fabric. The face fabric balances wind- and- water resistance with necessary ventilation. Arc'teryx outfitted the Proton LT with a collar height that provides extended coverage. The No Slip Zip front zipper prevents self-opening during high-output activities. The hem has dual adjusters that tighten to block cold updrafts. The exterior hand pockets are insulated, and the zippered chest pocket serves as storage for your phone or map. This trim-fitting jacket weighs only 355-grams, delivering performance as a standalone or mid layer for climbing waterfalls and backcountry tours.

• Fortius Air outer fabric
• Coreloft Continuous 65 insulation
• Collar height for coverage
• Dual hem adjustments
• One chest pockets
• Weighs 355-grams
• Trim-fit
• Arc'teryx Ascent Collection