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Perimeter Technologies

Perimeter Technologies Four Pack Dog Fence Batteries for Invisible Fence R21 or R51 Receiver Collars (4-Pack)

  • Based on 2,644 reviews
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Availability: Only 10 left in stock, order soon!
Fulfilled by Amazon
Arrives Sunday, Jul 12
Order within 10 hours and 37 minutes
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Features

  • Perimeter Technologies offers a cost-effective solution by providing a compatible replacement battery designed for Invisible Fence brand receiver collars, specifically the R21, R22, R51, and Microlite models.
  • Perimeter Technologies has innovatively engineered a battery to seamlessly replace your current one in the collar models listed above.
  • These batteries incorporate advanced lithium-ion technology, boasting a superior energy density while keeping your dog's electric dog fence collar lightweight.
  • Equipped with robust components, this battery delivers extended durability and enhanced safety features compared to standard batteries. It also remains waterproof when securely sealed within your collar using a tight rubber waterproofing seal.

Description

Perimeter Technologies saves you money with your compatible replacement batteries for Invisible Fence brand receiver collars. Why pay the hefty prices of their batteries when you can buy a brand you can rely on for much less? Perimeter Technologies has designed a battery that will replace your current battery perfectly in R21, R22, R51, and Microlite models. With much effort placed in the making of your batteries, it is guaranteed you will get a great life expectancy out of your collar. Perimeter Technologies Batteries consist of a New and Improved Japanese cell lithium-ion and have a high energy density, also keeping the weight down from your dog's collar. With the components that make up this battery, it gives the power to last longer and has better safety factors than the normal battery. Bring confidence that your collar will last and go easy on your pocket by purchasing your battery.

Number of Batteries: 4 Lithium Metal batteries required.


Brand: Perimeter Technologies


Battery Cell Composition: Lithium Ion


Recommended Uses For Product: Invisible Fence brand receiver collars, specifically the R21, R22, R51, and Microlite models


Unit Count: 4.0 Count


Number of Batteries: 4 Lithium Metal batteries required.


Brand: Perimeter Technologies


Model Number: IFA-001-4


UPC: 617529331180


Manufacturer: Perimeter Technologies


Battery Cell Type: Lithium Ion


Voltage: 1.55 Volts


Reusability: Single Use


Compatible Phone Models: Invisible Fence R21 or R51 Receiver Collars


Unit Count: 4.0 Count


Battery Weight: 3.2 Grams


Item Dimensions: 2 x 4 x 4 inches


Item Weight: 9.07 g


Antenna Location: Invisible Fence brand receiver collars, specifically the R21, R22, R51, and Microlite models


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Jul 12

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
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  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • They work just fine
Size: 1 Count (Pack of 4)
They work great
Reviewed in the United States on May 13, 2026 by Debbie Eiken
    • Great Product / Works Well
Size: 1 Count (Pack of 4)
The original Invisible Fence Batteries are far too expensive and over-priced. These actually work well - and just as long. Although - they have gone up significantly the past year (like everything) - but they are still far cheaper. I am thankful this is an option.
Reviewed in the United States on October 10, 2025 by Theresa L.
    • back again
Size: 1 Count (Pack of 4)
Had used perimeter batteries for a few years and had no issues. Tried to save a couple of bucks on another brand that seemed to have decent reviews. First couple of them seemed ok, but then life battery life became shorter and one of the batteries actually apart before inserting. I am back to my old reliable perimeter batteries. Well made and dependable. Still way less than invisible fence battery prices, they are a bargain! ... show more
Reviewed in the United States on April 17, 2024 by gasman94
    • Seems a good value for my needs
Size: 1 Count (Pack of 4)
Giving 4 stars for now. Been using invisifence for about 10 years, the kids are well trained by now. Due to the cost, I don't always replace the battery right away. When my girl starts to go over the line (but not far), I know she needs a reminder and have to replace the battery. It was time and she was getting adventurous again. These are much cheaper than brand name. Even if they last less than a month, I'll consider it a good buy. ... show more
Reviewed in the United States on October 3, 2025 by LancPAGuy
    • Collar Fails with These Batteries
Size: 1 Count (Pack of 4)
Bought four of these batteries for our Invisible Fence brand collar, P/N 900-0025-02. As far as I know, these batteries are supposed to be compatible with this collar; perhaps the seller can let me know that's incorrect. I followed the directions on the package: remove old battery cap, wait at least five minutes, insert new battery cap, wait at least 10 seconds before testing. Upon initial insertion of the new, Perimeter-brand battery cap, the green LED on the collar blinks green several times, as expected, and the collar functions as expected – it beeps, and presumably provides a shock, when moved over the fence line. However, a couple of hours later – nothing, no beep and no shock. The only reason I checked whether the collar was functioning properly was because a couple of days after inserting the first of these battery caps, I noticed the collar's LED blinking red, which usually means the battery is low. I went through the process several times of removing the battery cap, waiting, inserting, verifying correct operation immediately after inserting the cap, and then finding it inoperative just a few hours later. I found the same behavior with three of the four batteries, both when I initially removed them from their packages, and re-testing them several times over the course of a few days. I ran out of patience and interest and have not opened the fourth. I put a meter on each of the batteries I tested and found the voltage to be the same as that of Invisible Fence brand batteries. The current was over 1,000 mA, which is the upper limit of the meter I used. I didn't have a brand new IF brand cap to measure, but for the sake of comparison, an Invisible Fence cap that we removed because the collar's LED was blinking red, showed between 600 and 700 mA. I noticed a physical difference between these caps and IF brand caps. On IF brand caps, the surface of the negative contact of the battery, which is the inner circle of exposed metal on the business end of the cap, is flat and it's pressing firmly against the underside of the circular lip that holds it in place. That is, it does not receded when I push on it with, say, the tip of a ball-point pen. On these Perimeter brand caps, there appears to be a creased piece of metal under the retaining lip. The crease in this piece forms a diameter across the inside. This piece of metal is loose – you can feel and hear it move around a little when you shake the cap. I'm wondering if the contact between this conductor and the negative contact of the actual battery, on which it presumably rests, is intermittent, as the dog moves around. If so, perhaps the collar senses the loss of power, shutting itself during the milliseconds while the power is draining. If one is supposed to wait five minutes before inserting a new battery cap because the collar's capacitors have to drain completely before it will properly "boot up" again when power is re-applied, perhaps the jostling of the collar continually makes and breaks the circuit quickly enough that the collar won't start to operate correctly again until the contact is broken for the span of the five minutes. Just a theory that fits the observations; I have no idea of its accuracy. I also wonder why the height of the battery inside these Perimeter-brand caps appears to be less than that of the batteries in the IF-brand caps, necessitating the use of the creased, metal conductor. I've disassembled IF-brand caps (but never a Perimeter-brand cap) in the past and found that the full interior height of the caps occupied by standard batteries. Is the battery in the Perimeter-brand cap shorter? Does this mean that it contains less potential chemical energy to convert into electricity, i.e., will it not last as long, even if it functioned properly? I wrote and submitted this review before contacting the seller in an effort to save others from the same frustration. If the seller responds and somehow rectifies the situation, I will certainly submit an update. ... show more
Reviewed in the United States on October 10, 2014 by sabeq
    • Wireless fence batteries for the frugal
Size: 1 Count (Pack of 4)
Works great in his collar and keeps him on our property
Reviewed in the United States on April 20, 2026 by Linda
    • Works
Size: 1 Count (Pack of 4)
Works as advertised
Reviewed in the United States on May 16, 2026 by Linda LeClair
    • Great fit
Size: 1 Count (Pack of 4)
Worked perfectly for my dood's collar
Reviewed in the United States on April 2, 2026 by Sarah

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