The Delta 5 is the next step in a long line of remarkably reliable, durable, and smooth-breathing regulators bearing the name. Sure, we've given it an update, but that's not all. Like the Deltas before it, the 5 comes standard with our patented Dynamic Adjustment technology, dive/pre-dive controls, and a super-comfortable orthodontic mouthpiece. Unlike its predecessors, the Delta 5 has a metal pneumatic valve, which ensures exceptionally smooth breathing in any situation. We also included a heat exchanger on the hose connection to the second stage to further enhance the already excellent cold water performance. We paired the Delta 5 with the eDX. This top-of-the-line, overbalanced, top-of-the-line diaphragm first stage is environmentally sealed and features four low-pressure and two high-pressure ports. It's also equipped with a heat exchanger for additional cold water performance.