Our toasty, breathable Ridge 100 is a super lightweight pullover for its warmth. It contains Primaloft Bio which will mostly biodegrade* when it reaches the end of its lifecycle and is discarded in the right environment. This updated Ridge is a much improved traditional midlayer polar fleece that will become your go-to. Part of our innovative Ridge Styles. *93.8% biodegradation in 646 days under ASTM D5511 conditions (being optimal conditions that may be found in some biologically active landfills). The stated rate and extent of degradation do not mean that the product will continue to degrade. The fabric does not biodegrade in an environment with oxygen. Once disposed of, the product may not end up in a biologically active landfill without oxygen. Do not litter in nature.