The ScubaPro R105 Octopus is an alternate air source built on a downstream second-stage design. As an octopus, its job is to be ready when your buddy needs air, and the R105 keeps that role simple, with a mechanism that breathes well when it counts.

It has a VIVA (Variable Inhalation Volume Adjustment) dive/pre-dive switch, which lets you reduce free-flow at the surface and then open up the airflow for easy breathing underwater. The hose attachment is reversible, so the octopus can be set up for either left or right routing on your rig.

It is finished in the bright yellow that marks an alternate air source, which makes it easy for a buddy to spot in an out-of-air situation. For recreational divers in India who need a hard-wearing octopus to complete a regulator setup, the R105 is a sensible pick.