Techy On-trail Comfort, Easy Off-trail Casual—our Short-sleeved Merino Bike Jersey Fits Like A T-shirt But With Bike-specific Tailoring And Soft, Quick-wicking Merino Wool/Recycled Polyester Fabric. All Of The Virgin Wool Patagonia Sources Is Certified To The Responsible Wool Standard (Rws) To Help Ensure Protection Both For The Animals That Supply It And The Land They Graze. Fabric Is Certified As Bluesign® Approved. Fair Trade Certified™ Sewn.