Fit Guide We recommend sizing down for a better fit (e.g. if you're typically a medium, get a small). Benefits One of John John's essentials at home on the North Shore. Yamamoto foam rubber is ultra-stretchy, durable and premium. Performance patterning delivers a better, more secure fit. Lower collared design is more comfortable and doesn't flush. Boardshort tie locks down the jacket in heavy water. Burgee heat transfer on left arm. Flatlock stitching sits flush with the skin to prevent chafing during long sessions. Details 100% Yamamoto foam rubber The 1.5MM Flatlock Wetsuit Jacket is an elevated take on the everyday wetsuit jacket. Made with premium Yamamoto foam rubber, this jacket is ultra-stretchy & durable. A flatlock stitch design sits flush against your skin to ward off chafing during long days in tropical water.