PetSafe 3-Volt Lithium Battery Module, RFA-188

CHANGE THE BATTERY YOURSELF FOR 3 BUCKS!
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...
Buy replacement batteries yourself.
The Petsafe RFA-188 can be DIY replaced by opening up the bottom cap. It is glued so you'll have to use a plier. Underneath it you'll find a Sanyo CR-1/3N battery that can be purchased online for 3 dollars. I plan on buying a bunch in bulk to make shipping worth it, slap it in and use some glue or tape to put it back together. To find the inner Battery, just google it.

This is what it looks like but you can find it cheaper elsewhere on the internet.
Sanyo CR-1/3N CR-1/3N Photo Lithium Battery
Yes, Replace it Yourself
Following advice from other reviewers, I took the module apart and removed the battery. I'm not a handy person but there was nothing to it. I just ordered six replacement batteries online for less than what Petsafe charges for two. Considering how fast they burn out, buying them for my two cats from petsafe would cost me over $100 a year. This way it will be less than $35.
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