Yamaha Four-Stroke Jacket - Blue - Large The Yamaha 4-Stroke Jacket by FXR provides warmth and comfort from the elements with FXRs MMT Two Stage Dry Technology. Durable 300/420D nylon with HydrX, 10,000mm waterproof 8000g/m breathable laminate, Inner lining with Climate Management System, Removable zip-out 200g Thermal Flex insulation, Durable #5 YKK Vislon front zipper, Cold-Stop multi-placket magnetic front closure, Inner chin placket, Velcro tab adjustable collar, Chest vents with integrated Dry Vent inserts, Two front zippered hand pockets, Left sleeve key pocket