S3A(R) silver antimicrobial technology For odor prevention Ripstop cotton/poly/spandex fabric For function and durability Lightweight insulation Provides quiet comfort and warmth Comfortable rib knit collar Delivers a secure fit Great for layering For added warmth The Evolve vest sets a new bar with a reversible design that extends over multiple seasons. Extremely tough brushed faces allow this gear to be tested hard in the field day-after-day and month-after-month. The reversible Evolve is the workhorse you've always wanted.