The Lubell Labs underwater speaker has become the most popular underwater loudspeaker in the world since 1968, as it is louder and clearer than any other competing product. Its unique design (U.S. Patent #3391385) utilizes its dual-piston PVC overmolded aluminum enclosure as the sound transducer, offering true pistonic operation with no exposed metal parts. Coupled with a powerful 8-cylinder piezoelectric engine (with efficiencies approaching 60% in a corrosion-free design).