Medium Weight Human Form Jacket - Yellow/Orange 8 oz. polyester or poly/cotton twill treated with durable water repellant plus an added wind barrier of tightly woven polyester or nylon. Insulation is 3M G100 Thinsulate or equivalent, add the optional 747 liner vest and this becomes a Heavy Weight Jacket, lining is nylon satin. Reflective is 3M Scotchlite Reflective 6187 or Reflexite GP350. Sizes medium+ are ANSI Class 3, size small is an ANSI Class 2 garment.