This is the Aqua Helix Compact Pro Scuba Diving Octopus Features: The light and small Helix Compact Pro is Pneumatically-balanced resulting in smooth and easy breathing The in line venturi lever prevents unwanted freeflow at the surface while giving a performance boost at depth Includes 1m yellow hose and yellow front cover making it easy to locate in an emergency Heat exchanger (patented) which surrounds the valve mechanism, dissipates the cold caused by gas expansion while drawing in the warmth of the ambient water Pneumatically balanced Controls Venturi switch Breathing resistance Preset Heat Exchanger for freezing resistance 2nd Stage Weight 200 g Hose length 1000 mm Overall work of breathing (WOB) scores Avg. 1.35 joules/liter with Helix Pro 1st stage Nitrox compatible Yes, to 40% O2 when new, out of the box The Helix Compact Pro Octopus provides the same great performance as the Helix COmpact Pro primary second stage. This small compact and friendly octopus is the one you want to take on your next dive trip.