This is the Aqua Lung 1.5mm Seavest Hooded Vest for Scuba DivingFeatures: A bubble vent is built into the hood to allow trapped exhaust bubbles to easily escape 1.5 mm skin-in-face seal which is designed to be easily trimmed Durable and comfortable flatlock stitching The SeaVest is a popular accessory to provide additional warmth to any of our jumpsuits, and comes in two thicknesses, 1.5mm or a combination of 4/6 mm. The 4/6 mm version is made with various thicknesses of Super-stretch neoprene to provide maximum insulation in high heat-loss areas. "