The pedal-powered Scubster submarine is certainly the greenest source of underwater locomotion you've ever seen, if not the most cutely named. The Scubster is designed for shallow ocean and river excursions, and produced with millionaires in mind: the creator believes it may capture the imagination of owners of super yachts and the like.
The exclusively pedal powered Scubster submarine requires the driver to wear an oxygen tank, limiting the time underwater. I think I'll have to pass on this purchase, but I can see the attraction of a pocket submarine to fool around with.
Pocket Pedal-Powered Submarines
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