i-gotU GT-120 Travel Blog Master (USB GPS, Data Logger, SiRF III Chipset) (Bumper Case, Data Cable and Software Included) Larger memory capacity for long trips: 64,000 waypoints. 4 times memory then GT-100 30% less power consumption vs GT-100. Faster satellite acquisition: &lt;35 sec vs 60 sec with GT-100. Make sure your digital camera time is correct. Power on the GPS Travel Logger outdoors. Wait auto-positioning and locate your current position. Take the GPS Travel Logger with you when taking photo. PC with Windows 2000, XP, Vista. PC with USB 1.1 or 2.0.