This is the Oceanic VTX Wrist Scuba Diving Computer with USB Features: Bluetooth ready for wireless transfer of dive profiles and dive computer settings. Compatible with soon-to-be-released PC, Mac and iOS applications Advanced features for today's technically-savvy diver, yet comes out-of-the-box-simple for new or less frequent divers Powered by Dual Algorithm allowing you to choose the decompression algorithm that best suits your diving needs without compromising safety Hoseless air integration with patented Air Time Remaining Algorithm provides calculations in real time, allowing accurate gas management 3-Axis Digital Compass with Full Tilt Compensation Up to 4 Nitrox mixes - each with individual PO2 set points Automatic Safety Stop Countdown Optional Deep Stop with Countdown Timer Intuitive push button menu interface with Step Back" allows for easy settings preview and edits while viewing the menus Firmware Update Ready User Replaceable Battery with 30-40 dive hour life*. Data Retention maintains settings and calculations between battery changes Transmitter NOT included Cutting edge technology coupled with powerful features could not be any easier to experience. A hoseless, air-integrated computer with patented air time remaining algorithm. High contrast OLED color screen, tilt compensated 3-axis digital compass, Bluetooth ready, up to 4 nitrox mixes, user replaceable battery and an intuitive push button menu system. "