Patagonia R1 Yulex Front Zip Wetsuit - highly elastic wetsuit with warm thermal lining. Patagonia's neoprene-free Yulex® wetsuits are made in a Fair Trade-Certified™ factory and consist of 85 % natural rubber and 15 % synthetic rubber by polymer content. They replace a petroleum-based material with a vegetable-based material and offer the same warmth and performance characteristics as conventional stretch neoprene. At the same time, they reduce CO2 emissions in the manufacturing process by up to 80 %. Manufactured from materials certified by the Rainforest Alliance Forest Stewardship Council®, Patagonia mixes natural rubber with chlorine-free synthetic rubber to enhance ozone and UV resistance and to meet its stringent strength, elongation and durability requirements.