The Sentinel is an electronics-driven fully closed circuit constant PO2 design rebreather (eCCR) that provides an intelligent and easy to use life-support system (LSS).

Manufactured in the United Kingdom (UK) by VR Technology Ltd, the Sentinel provides the user with a simple Check-and-Dive™ functionality that makes the rebreather the quickest and safest rebreather life-support system to prepare for diving.

It uses intelligent monitoring and design experience to determine the appropriate tests and checks. Any problems or remedial action are described clearly on the full-color graphics screen.