The Petrel 3 is  standalone wrist computer and DOES NOT have any method of directly monitoring O2 cells for rebreather systems.  If you need direct montoring of cell then please consult your CCR manufacturer and determine if they require Fischer or AK Pin wires which are used for external PO2 monitoring of up to three oxygen sensors in a rebreather loop.

The Petrel 3 from Shearwater Research is a full decompression dive computer incorporating the Bühlmann ZHL-16C algorithm, with user configurable Gradient Factors (GF). Gradient Factors allow the diver unique and individual control of their dive computer decompression calculations. An optional PIN upgrade to the Varying Permeability Model (VPM-B and VPM-B/GFS) decompression algorithm is also available (the DCIEM algorithm is not applicable to rebreather modes.) The Petrel 3 includes a richly featured 'gauge mode' configuration, along with a three-axis tilt-compensated digital compass. The included CCR mode for rebreathers provides the ability to perform constant PO2 set point calculations for deco.

During a decompression dive, the Petrel 3 provides complete information displays of all required stop times. The Petrel 3 can provide time-to-surface based on "look ahead" at planned gas switches. Multiple gas definition presets are supported with any combination of oxygen, nitrogen and helium. The Petrel 3 will NOT "lockout" after a missed stop or ascent rate violation. Out of the box, all models include open-circuit and closed-circuit Air, Nitrox and Trimix mixed gas functionality. The Petrel 3 offers a screen display utilizing a low-power consumption, high resolution QVGA, full color LCD display. The display will automatically adjust intensity based on available light to make the display easily readable whether on the surface in sunlight, in open water or in a cave.

The Petrel 3 is capable of wirelessly connecting to optional SWIFT transmitters giving the diver ability to monitor up to four tank pressures. It is also capable of calculating the Gas Time Remaining (GTR). Air integration is optional for all modes, from OC Rec to CC/BO. The tank pressure(s), in PSI or BAR, and GTR can be displayed to the customizable slots on the main display screen or accessed through the underlying information screens. Enabling the AI feature causes approximately 10% decrease in battery life. The AI base price does not include a tank pressure transmitter because the consumer may already own a compatible transmitter. You may include transmitters during purchase or add them at a later time.

The Petrel 3 has been designed to accept any type of AA size battery including alkaline, lithium, SAFT and rechargeable. Included with every Petrel 3 from TridentWarriors are two elastic straps with buckles, gold contact battery holder and battery already installed (ready to dive out of the box!). The Petrel 3 also includes a titanium bezel and a screen protector already installed to help prevent scratches of the display face. The software includes a complete dive log manager, compatible with both MS Windows and MAC OS X, and can be downloaded from Shearwater's website along with the manual. The dive log manager supports log downloads and firmware updates via the Bluetooth wireless interface of the Petrel.

It also includes a USB Bluetooth adapter, mini-CD with Petrel Manual (PDF) and printed Quick Start Guide with instructions for downloading software from the Shearwater Research website, the Fischer 103 connector, cap, and small bottle of mineral oil. 

NOTE: The Petrel 3 does NOT include a cable and sensors, that is a custom solution which must be supplied separately for your specific brand and model rebreather.

Modes

• Air
• Nitrox
• 3 Gas Nitrox
• OC Tec - Multi gas, trimix decompression computer
• CC/BO - Closed circuit fixed PPO2
• Gauge - Bottom timer with stop watch and dive logging