Set it and forget it. The last thing you need to worry about on the dive is your breathing system. The GT 3 puts you in total control with its patented Dynamic Adjustment feature. Whether you're snorkeling to your dive site or working a current on your favorite deep wreck, you can quickly adjust the GT 3 to behave precisely the way you want, then let it do the work as it automatically readjusts with changes in depth.

How to Read Work of Breathing Charts
The computer-generated breathing machine chart presented above represents a regulator's performance per standards established by the U.S. Navy's Experimental Diving Unit. Tests are conducted at 198 feet with approximately 3000-psi supply pressure, 25 breaths per minute of 2.5 liters each.

(1) Inhalation - The chart shows one complete breath cycle, starting with inhalation on the left and continuing along the bottom to the right, staying mostly below 0.0; thus the inhalation work of breathing is reported in negative numbers.

(2) Exhalation - The exhalation effort begins on the right and runs across the top to the left. These are all positive numbers since a diver (or the machine in this case) is blowing out (exhaling) rather than inhaling.

(3) WOB - The total area inside the loop formed by the two lines is what the computer analyzes to calculate the regulator's total work of breathing - the amount of energy the regulator requires to move each liter of air.

*Column Inches of Water

Diver adjustable inhalation effort
Most downstream demand valve regulators are calibrated during manufacturing to a single, 'middle of the road' operation. Whether finning up current at 100+ feet or merely snorkeling out to the dive site, this factory adjustment may not be optimum for the wide variety of demands we place on our equipment. A simple twist of the GT 3's adjustment knob enables complete control...set the inhalation requirement to near zero when you need ultimate performance, or tune it for greater resistance
as conditions or preferences change.

Patented Dynamic Adjustment
A common objection to adjustable second stages is that divers can't imagine themselves twisting and turning a knob as they descend and ascend through the depths. If inhalation resistance is set near zero at depth, your ascent would require you to manually increase resistance as ambient water pressure is reduced to prevent free-flow. Taking another stride beyond common second stage engineering, Oceanic designed a patented DYNAMIC ADJUSTMENT feature into the heart of the GT 3. This mechanically balanced valve maintains a preferred breathing resistance throughout the dive. Set it once and the GT 3 automatically adjusts to make breathing as easy at 100 feet as it is at 30 feet - with no additional manual adjustment.


Computer optimized design
Oceanic regulators are exclusively designed using the latest 3-D computer modeling techniques. This allows us the ability to model and test performance while still in the early stages of development. The GT 3's unique deflector vane and housing design diverts airflow from the valve directly to the mouthpiece, producing smooth venturi-assisted inhalation.

Lightweight
The GT 3's housing is made from an ABS/Polycarbonate composite blend of materials making the Delta 3 both extremely rugged and lightweight (5.8 ounces) and nearly neutrally buoyant underwater, reducing jaw fatigue on extended dives.

Patedted orthodontic mouthpiece
To further reduce jaw fatigue, the GT 3 features a patented Orthodontic Mouthpiece, designed to accommodate the natural overbite of the human jaw.

Nitrox Compatibility
The GT 3 is classified as being suitable for use with nitrox breathing gas mixtures containing up to 40% oxygen by volume without the need for special preparation, cleaning or component parts.