Chris Kennedy built an manually controlled closed circuit rebreather based on the Dolphin Semi closed unit. The dosage unit connects to the exhale bag at the same place the over pressure relief valve is on the SCR version. Dilutant is fed to the dosage unit acting as an ADV now via a standard 1st stage. The Oxygen side is fed into the dosage unit using a Pelagian feed and needle valve. Chris is in the process of producing one for this unit. The Dolphin MCCR was test dived by Rod a couple of weeks ago on the Cedar Pride wreck and it proved worthy of further refinements. Chris has now tested the unit to a depth of 35m and everything worked OK. Pics below taken at First Bay and the Power Station Wall where the unit was put through its paces