 Unlike back-mounted cylinders, the sidemount diver has immediate access to, and can see, the regulators and tank valves of their cylinders.This enables quicker and more certain problem identification and resolution, without requiring ‘behind the head’ shut-down drills that require a higher level of joint and suit flexibility and the ability to identify and correctly operate equipment which is out of sight.Sidemount diving configuration places the cylinders under the diver's armpits, in line with their body, allowing the diver to pass through smaller restrictions than would be possible with back-mounted cylinders.