This is the Shearwater NERD 2 Near Eye Remote Display Standalone Features: Rebreather tested. Rechargable Battery Refined Compact Design 2 Button Interface 1000 Hour Dive Log OC Recreational - Three gas nitrox computer with features for the serious recreational diving enthusiast. Includes adaptive safety stop and NDL bar graph 5 OC gases Trimix enabled by default External Monitoring - Real time PPO2 monitoring of 1 - 3 O2 sensors Digital Compass - Optional 3 axis, tilt compensated, digital compass Gauge - Depth, time, resettable stop watch function Full dive logging Rechargeable Battery - With a minimum of 18 dive hours on a full charge with medium brightness (recharge time 4 hours). wo Button Interface - Simple to navigate, state-aware menu structure. Digital Compass - Optional 3 Axis, tilt compensated, digital compass. Bluetooth Integration - This enables communication with Mac, Windows, iOS, and Android with lower power consumption. This allows connection to Shearwater Cloud. Mount Options - The 2 hole patterns allows for custom mount designs and compatibility with NERD 1 mounts. Modes OC Rec 3 gas nitrox recreational computer OC Tec Multi gas, trimix decompression computer CC INT Closed circuit fixed PPO2 CC EXT (Fischer only) Closed circuit real time monitoring of 1 or 3 O2 sensors SCR EXT (Fischer only) Semi-closed monitoring of PPO2 for 1-3 O2 sensors Gauge Bottom timer with stop watch and dive logging The world's first near eye remote display for scuba divers has been redesigned for enhanced flexibility and reliability. In addition to the DiveCAN and Fischer versions, OC divers can now experience the freedom the NERD 2 has to offer. The universal regulator mount allows divers to secure the NERD 2 to their mouthpiece and dive with the security of knowing their crucial dive information with a glance of the eye. From the combination of the Micro LCD display and the magnifying lens, the data on the NERD 2 appears as if you were looking at a 25 inch TV 12 feet away. "