This is the description from Suunto website:
The Suunto Vyper2 includes Gauge and Nitrox modes with the added feature of gas switching. For divers using enriched air, the Suunto Vyper2 can be programmed in one-percent increments for nitrox mixtures between 21 and 100 percent oxygen. Divers can also adjust oxygen partial pressure between 0.5 and 1.6 bar in 0.1-unit increments. Adjustments can be applied to both mixes. The Suunto Vyper2 uses the Suunto Deep Stop RGBM algorithm, that features continuous decompression for optimal ascent time. For deeper dives, the Deep Stop option adds further protection with a series of "deep stops" between your maximum depth and ceiling. The Suunto Vyper2 boasts a built-in dive simulator, allowing you to test potential dives before dropping into the water. It also features large digits and a new Matrix display that clearly shows critical dive information including dive profile graphs. After the dive, you can download the data to your PC and easily maintain a detailed logbook.