The newly updated Patagonia R1 Lite Yulex Long-Sleeve Top delivers the same eco-friendly construction as its predecessors, but now features even more stretch and comfort at a reduced weight. The 1. 5mm Yulex natural rubber blend provides insulation against cool spring waters, and does so without the harmful effects that come with traditional neoprene. Patagonia attributes its use of Yulex rubber to a whopping 80% decrease in CO2 emissions during the manufacturing process compared to standard neoprene-based wetsuits. It's also sourced from a Forest Stewardship Council (FSC) certified rubber plantation in the highlands of Guatemala, giving Patagonia total oversight over the production process in order to maintain the highest degree of environmental and social responsibility--all without deforesting sensitive ecosystems. And there's more to love about this top than its planet-benefiting construction. A flexible and quick-drying recycled polyester lining lends easier movement and greater comfort while you surf, while the flatlock seam construction reduces chafing within the tight anatomical fit. A rubberized waist gasket with an adjustable waist and cord-lock help keep the water out and your top in place, ensuring that you won't be fidgeting with your fit as the day's best wave passes you by.