The Sidekick is a mechanical rebreather, so there are no electronics controlling the gas addition to the system.

Both the head and scrubber is placed inside a large single counterlung, which in turn is housed within and protected by a cylindrical shaped stainless frame, making for a small and lightweight rebreather with fewer parts and less complexity than diving a fully closed circuit rebreather.

Without the loop hoses, the unit measures 21.25 inches (54 cm) in length by 7.25 inches (18.4 cm) in diameter.

By shunting a portion of each exhaled breath back into the loop, this device will extend the duration of a given gas supply by a factor of three. The benefits of this type of gas-extension provide advantages for both recreational and technical diving. Note that proper training outside the level 1 GEM Sidekick course is required prior to doing any technical diving.