APEKS DB4+ 1ST STAGE ONLY
PRODUCT DETAILS
Cold-tested heritage. Compact form. Depth-stable delivery.
BACK IN STOCK FEB 2026
The Apeks DB4+ First Stage brings the proven backbone of expedition regulation into a streamlined, stand-alone 1st stage that’s born for temperate and cold-water diving around the United Kingdom.
Machined from brass on the trusted DS4 blueprint, the DB4+ delivers the rugged simplicity divers rely on, but with smarter thermal resilience and improved routing logic — making it ideal for divers who want premium primary performance without a bulky profile.
Smarter physics on descent
At its core is an over‑balanced diaphragm architecture that increases hose pressure faster than ambient pressure rises as you go deeper. The result is stable gas delivery, smoother breathing response, and reduced performance drop-off at depth — keeping flow strong when the dive transitions from “fun” to “focused”.
Cold-water stability reclaimed from the sea itself
A large-surface heat-exchange diaphragm clamp reintroduces warmth into the gas path, increasing internal gas temperature and reducing freeze risk where it counts. This isn’t just cold-compatible, it’s cold-considered engineering — appreciated most in northern layers like the North Sea or winter-timed quarry profiles.
Impact protection without adding bulk
The breakthrough over-moulded 1st stage endcap and environmental diaphragm don’t just resist ice build-up, they shield the spring chamber from water, silt and impact damage between dives. It’s protection you feel in durability, not in drag.
Future-sensible hose routing
With 2 high-pressure ports and 4 medium-pressure ports, routing is clean and practical, supporting SPG hoses, wireless transmitters, inflators, or suit feeds without stress or sharp hose bends. The angled HP geometry makes transmitter alignment natural and snug when pairing with compact dive electronics.
DB4+ 1st Stage Highlights
✔ Ultra-compact, precision-machined brass body
✔ Over-balanced pressure delivery that improves with depth
✔ High-surface-area heat exchanger clamp for cold-layer stability
✔ 2 × HP + 4 × MP ports for clean, logical hose orientation
✔ Ice, silt and impact protected by over-moulded architecture
✔ Expedition-bred platform reliability
✔ Built for UK and cold-temperate water
Less drag. More warmth. Stronger at depth.
The 1st stage that works quietly — and delivers loudly.
Breathe deeper. Dive longer. Rig smarter. 🤿