Brownie's Third Lung of Fort Lauderdale, Florida, manufactures surface-supplied air systems for sport and commercial purposes, as well as Scuba tank fill compressors and Nitrox fill systems. Brownie's multi-faceted approach to water sports is a result of experience, research and building a facility that leaves nothing to chance. Check out their site for more info on their products.
Marine Technology Development of San Jose, California, produces the Frog and Gator closed-circuit SCUBA systems. This comprehensive site contains info on both models, as well as history of the rebreather, background on the company, training and lots more.