Scuba air cylinders are typically big heavy things that can can't easily be carried long distances. The Smaco S700MAX system is different, in that it incorporates a compact cylinder that snugs into a custom BCD which doubles as a backpack.
Made of 6061 aluminum alloy, the S700MAX cylinder has a capacity of 1.9 liters and can be filled to a maximum pressure of 3,000 psi (200 bar). It measures 360 mm tall by 111 m wide (14.2 by 4.4 in), and tips the scales at a claimed 2.9 kg (6.4 lb) when out of the water – it's neutrally buoyant underwater.
According to the system's Hong-Kong-based designers, one fill should be good for 30 to 45 minutes of underwater breathing time, depending on usage. That said, prospective buyers should note that the cylinder is depth-rated to just 33 ft (10 m) … so yes, there is a tradeoff. The cylinder can be filled either from a dive store compressor, from a larger traditional air cylinder, or via an optional Smaco electric compressor.
Two of the cylinders can be mounted side-by-side on the included BackPro BCD (buoyancy control device), where they share a common regulator, pressure gauge and inflator hose. And while the cylinder and BackPro have been designed to work with one another, the cylinder can be mounted on other BCDs, and the BackPro can accommodate third-party cylinders of up to 12 liters in capacity.
When loaded with one or two of the S700MAX cylinders, the BackPro can be converted into a fully enclosed backpack for carrying the whole rig on land. A storage compartment in that pack is used to carry items such as a mask or dive gloves.
The S700MAX system is currently the subject of a Kickstarter campaign, where a pledge of US$949 will (hopefully) get you a setup that includes a cylinder, BackPro BCD/backpack and refill adapter. The planned retail price for that package is $1,299, which does not include the regulator – it has to be added as an extra. Rather frustratingly, there currently appears to be no way of buying two full-capacity 1.9-liter cylinders without also buying two BackPros.
The system is demonstrated in the following video.
Source: Kickstarter
