The basic model was called the Sea Land Splash Twin, it had two air-filled tanks; the other features listed in the technical data sheet on this site, and was known thanks to James Bond. Then the idea came up to make it a little more performing in terms of autonomy, transforming it into a microrebreather called Eoba - Enriched Oxygen Breathing Apparatus.
The image above clearly shows the operating diagram, with the two hose surrounding the diver's head and containing the soda lime filter located behind the neck. At the front are the system to prevent CO2 recirculation and the valve to release any water that may have entered the hose, while between the two mini-tanks, a gauge indicates their residual pressure. It's cute, but James Bond was probably satisfied with the open-circuit model, so this remained in the drawer of its designer's dreams.
__________