Aftermarket Replacement Battery Caps compatible with the Invisible Fence® Brand R21, R22, R51, & MicroLite™ receiver collars.

Aftermarket batteries so good, they're patented. Perimeter Technologies has redesigned and has a patent pending on an improved version of the once exclusive Invisible Fence Power Cap®, providing customers of the nation’s largest and best known professionally installed dog fence company a less expensive but substantially better battery replacement alternative.

Click here to find out why these batteries are just as good or better than the original! 


So save yourself some money and free yourself from that expensive Invisible Fence® Brand battery plan you are on from your local Invisible Fence® Brand dealer! We have batteries to fit your Invisible Fence® Brand collar as low as $8.95! (when purchasing the 12-pack) Shipping is FREE.  These batteries are guaranteed 100% compatible with your Invisible Fence® Brand R21, R22, R51, & MicroLite receiver. Our batteries batteries are an exact aftermarket replacement to the Invisible Fence® Brand Power Cap® battery. Satisfaction guaranteed! You’ll get quality batteries manufactured right here in the USA by Perimeter Technologies, Inc (not manufactured by Invisible Fence, Inc.). All of our Invisible Fence® Brand compatible batteries meet or exceed the original manufacturer’s specifications. Many dogs report getting a 6 month battery life out of each of our Invisible Fence® Brand compatible batteries. The shelf life on these batteries is at least six years.




Perimeter Technologies, Inc. (Manufacturer) and (retailer) do not represent that they are affiliated with the Invisible Fence® company in any manner. The replacement batteries listed on this site are not Power Cap® batteries, rather they are an aftermarket exact replacement for the Power Cap® battery. Invisible Fence®, Power Cap®, & MicroLite™ are registered trademarks of the Invisible Fence, Inc. Perimeter Technologies® is a registered trademark of Perimeter Technologies, Inc.