*PLEASE READ!!* This is a blocked IP Apeks DS4 DIN first stage. This is intended for use with a CCR unit for oxygen delivery. If you are not familiar with what a "blocked" first stage is intended for, please DO NOT PURCHASE this regulator. A blocked first stage keeps the intermediate pressure from increasing with depth which will be a problem if you are using this regulator for open circuit scuba and relying on it for breathing. I do not have the parts removed prior to being blocked. It is upgraded with the apeks "beefy" spring and blocking cap. This was previously in use on a sidewinder CCR unit as the oxygen bottle first stage. It has seen VERY little use and is oxygen clean and ready to be used.
