Jack Flash has a sealed hull construction. There are batteries at the front which counter-balance the weight at the back end so the two are equal and counter-balance around the centre point. It has a set of three motors that are geared so that they drive together. The motors are small and slim but by using three together, more power is generated to drive the robot's driving band. This driving band in turn powers a crank. The remote controlled steering mechanism controls the pivot of the crank. This is what produces the left and right steering by causing the tail to flap either in way or the other. The robot uses a standard remote/radio control which works under water for up to a depth of ten feet.