OK, so scrolling through the reviews here there are endless 1-star, "the battery dies in a month reviews". No kiddin! We saw it the first, second, third, fourth, etc... Time! I had a Petsafe collar with a red blinking light... I took out the Petsafe battery and figured out what needed to be done to replace it within a minute, so can you. When you remove the battery, the positive terminal (silver top of the battery with a "+" on it) will have a plastic ring around it that holds the battery in the holder. If you look carefully, you will see a couple of tabs and a seam that runs around the top lip. Just use a small screwdriver, or pocket knife to pry this ring off. It will break off...No matter - it was only glued on to begin with. Now get a pair of needle-nose pliers and grab gently along the side of the battery (where metal is exposed on the sides)... It may take a tiny bit of force to pull out, but it came right out for me. Now install a new Sanyo (or other brand) CR-1/3N battery (I picked one up at WalMart for $3.OO) by pressing it back in. You don't need to worry about gluing anything, it will hold just fine and will be that much easier to remove next month when it dies again. Now plug that joker back in and you're GTG. Petsafe makes a great product, but they should be ashamed of themselves for trying to sell this battery off as proprietary - BS!! Good Luck!