Bests & Worsts Reviews from Amazon

You can save a lot of money by using any regular (inexpensive) NiMH rechargeable AA batteries. Normally the device will refuse to charge them, but you can trick a Garmin Oregon 600 into thinking that you've got the special Garmin Battery Pack by putting a small piece of plastic underneath the batteries in the battery compartment. In the center of the battery compartment, there is a small button made from black rubber. When you put a thin piece of plastic on top of that button and then install the batteries on top of that, they will hold the plastic piece in place and it will keep pushing that button, which makes the device think you've spent a small fortune on the oh-so-special battery pack and it will charge the batteries while it's plugged in. I cut a rectangle about 1" x 0.5" from some clear plastic "clamshell" packaging. For batteries, I use Eneloop NiMH AA batteries. Otherwise there is no difference between the Garmin battery pack and any 2 high-quality rechargeable AA batteries.