An underwater motive device provides an integrated front cone and handle assembly with a mechanical link between the front cone and handle assembly to the main body of the unit which includes the battery compartment, motor, propeller and guard. The sealing between the cone and handle assembly and main body is accomplished by a double annular projecting seal having a rear ribbed portion extending deep into a slot in the main unit, and a forward more rounded ribbed unit which provides sealing in a front cone and handle assembly chamber. A battery cassette is provided for loading a number of commercially available flash light type cyclindrical cells, the battery cassette having an uneven pentagonal cross section so that it is inserted into a matching uneven pengagonal cross section within the main unit, but only where the battery cassette is of the proper orientation. The battery cassette also has a female plug which mates with a male plug extending from the rear of the battery cassette matching space within an opening in the main housing. A mechanical link enables handles located on the forward nose cone to mechanically communicate with a switch on the inside of the main housing through a flexible membrane on the seal.