Mego's vehicle line was expanding to include not only land rovers, but water craft too. 1976 saw the release of the Hydro Copter, based on the Microman Marine Copter from their "Mecha Cosmo" series. This was a multi-action toy that was battery powered, and could be used on land as well as in the tub or pool...and even in the air!

The Hydro Coptoer was a large boxed item that came with many accessories. As a land vehicle, it came equipped with 2 suspension bars which were a 2 piece leg that held a wheel with rubber tire onto the main body. The cockpit was made of a 2 piece clear bubble dome. The dome had pegs which suspended a chair (as it rolled along) that held a figure in place with a small rubber band. Fitting the 2 halves together, it in turn was held in place by a large black rubber tread. The tread helped the bubble roll along by touching the spinning gears inside the main body.
The gear action was powered by an "aqua motor" . The aqua motor was basically a casing that took a" penlight" , or A battery that, when the end section was turned clockwise, powered a small motor that spun a little gear. The aqua motor slid into the back part of the main body, inserted thru a tail cover cap.
2 red tail fins fit into 5mm holes on the tail cover, and when the motor was turned on (thru the hole in the tail cover end) it would also spin the large rotor blades. The blades were held by a rotor spindle which popped into the top of the main body. Other 5mm holes on the main body held 2 red laser guns.

As a water craft, 2 red paddles could be fitted onto either side of the bubble dome, and 2 white float bubbles replaced the fins on the tail cover. The aqua motor could then be moved to the underside of the main body and fitted with a small red propeller on the gear end. One final accessory was a large "U" shaped red arm. This could be attached to the bubble and aqua motor for a one man bubble craft. The versitality of this vehicle made it one of the more popular ones in the Micronaut line.
A brighter colored version and a more silver version was also released by the Hour Toy co. and M&D Toys respectively as the Cosmic Amphi-Copter. There was also one other vehicle Mego did not choose to release from the Mecha Cosmo series...