shell jacket in bioearth polyester . the oakley tc skull reduct shell jacket is made from innovative bioearth polyester, a material that biodegrades faster. the 2l fn dryâ„¢ membrane, in combination with the hydrofree dwr coating, ensures high breathability and protection against moisture. in addition, this shell jacket offers a waterproof front zip and pockets with waterproof zips. gadgets like the rfid pass pocket and design details like the skull patch round off this jacket.