Bob Hollis had his first rebreather experiences in the mid-60’s. He used Draeger units to allow him to get close to Sea Otters and other marine life in Monterey Bay. In 1970, Hollis made some of the first dives on the Electrolung rebreather using Heliox down to 300 feet in Honduras and Bonaire, filming ship wrecks and deep reefs. In 1990, Bob & Oceanic developed the “Phibian” rebreather, which at the time was the only commercially available unit.In 2000, under two separate contracts with the United States Naval Surface Warfare Command, Hollis developed and delivered a unit called the “ATUBA” (Advanced Tactical Underwater Breathing Apparatus). This solid back-ground of rebreather technology has led to the development of the Prism 2.