Increase your Galileo dive computer's versatility by updating your Terra or Luna to include SCUBAPRO's Predictive Multi-Gas (PMG) function. PMG lets you enjoy the benefits of carrying high 02 mixes in addition to your main breathing gas. With PMG your computer calculates the decompression schedule for all possible gas combinations and adapts the calculation accordingly. A PMG upgrade widens your underwater exploration opportunities by allowing you to use up to three nitrox mixes (21-100% O2) during the dive. Includes Galileo software upgrade key code for downloading.