Apeks DS4 DIN First Stage Regulator **BLOCKED IP!!**

*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.