Rated 4.90 out of 5 based on 30 customer ratings
(30 customer reviews)

$21.99

12V 8Ah Compatible Battery for APC Back-UPS CS BK350, BK350i, BK350Ei

Availability: In stock

SKU: ML8-121230111114 Category:
Delivering power when you need it, the Mighty Max ML8-12 12 Volt 8 AH uses a state of the art, heavy-duty, calcium-alloy grid that provides exceptional performance and service life in both float and cyclic applications.
The ML8-12 is an Absorbent Glass Mat (AGM) technology with a valve regulated design, that can be used in enclosed and indoor environments without leaking or maintenance, providing a superior performance for thousands of models.
Mighty Max SLA batteries are utilized in a wide variety of applications including; Consumer Electronics, Electric Vehicles, Engine Starters, Golf Carts, Hunting, Lawn and Garden Tools, Medical Mobility, Motorcycles, Power sports, Portable Tools, Solar, Toys and Hobby, Access Control Devices, Emergency Lighting, Security and more.
Specifications:
Voltage: 12 Volt
Amperage: 8 AH
Chemistry: SLA, AGM
Terminal: F1
Battery Dimensions:
5.94 in x 2.56 in x 4.02 in
Weight: 4.96 Lbs
Warranty
1 Year
Weight

4.96 Lbs

Height

4.02

Warranty

1 Year

Length

5.94

Quantity

1

Terminal

.187" – F1

Chemistry

SLA / AGM

Width

2.56

Amp Hour

8Ah

Volts

12V

30 reviews for 12V 8Ah Compatible Battery for APC Back-UPS CS BK350, BK350i, BK350Ei

  1. Rated 5 out of 5

    Guy H.

    I installed the battery 3 weeks ago and it has been working fine. No problems with the installation which took 3 minutes!

  2. Rated 5 out of 5

    Web Customer

    Way better than paying verizon 7X the price for the samething. Ding ding ding!

  3. Rated 5 out of 5

    Customer

    Way better than paying verizon 7X the price for the samething. Ding ding ding!

  4. Rated 5 out of 5

    jacek dabek

    Exactly what I need. Good battery for the money, fast shipping!

  5. Rated 5 out of 5

    jacek dabek

    Exactly what I need. Good battery for the money, fast shipping!

  6. Rated 5 out of 5

    michael krueger

    c

  7. Rated 5 out of 5

    Web Customer

    works great

  8. Rated 5 out of 5

    Customer

    works great

  9. Rated 5 out of 5

    SomeGuy

    Only none OEM lead acid I will get.

  10. Rated 5 out of 5

    JD

    Works as predicted. We’ll have to wait and see if it lasts like it should.

  11. Rated 5 out of 5

    Charles S.

    Using it for the Verizon Fios connection box.

  12. Rated 5 out of 5

    WareHaus Recording Studio,LLC

    Great battery, worked as soon as it was installed. This replace our old battery that was in the unit for about 7 years. Would buy again!!!

  13. Rated 5 out of 5

    Wart050

    I used this to replace the defective battery in my APC CS350 ups back up. As other reviewers have stated, the terminals do not match up but are usable.

  14. Rated 5 out of 5

    Jackie

    good price, good battery

  15. Rated 5 out of 5

    Joe Over Here

    Works great. What else can I say.

  16. Rated 5 out of 5

    Kenneth John

    A good, inexpensive and so far a very good product. Service is great with Mighty Max if you should have a problem with your purchase !

  17. Rated 5 out of 5

    Kevin Shipbaugh

    great.

  18. Rated 5 out of 5

    Customer

    Perfect fit. Terminals attached easily and slid right into the APC. Up and running in two minutes.

  19. Rated 5 out of 5

    GregSCSA

    This battery was a direct replacement EXCEPT the terminals were SLIGHTLY smaller. Even so – no adaptations had to be made; it was replace and back in service!

  20. Rated 4 out of 5

    TBGH

    Works as expected so far.

  21. Rated 4 out of 5

    drsuna

    Battery fit into the casing. The tab however, on the positive lead is smaller than the original. I have to improvised a bit to get it to work. Haven’t have a power outage yet sip don’t know how the battery holding up.

  22. Rated 4 out of 5

    ross

    perfect, fast shipping, would be 5 it the terminals were a little thicker like other batteries. but have thought three no issues.

  23. Rated 5 out of 5

    Piixel Pusher

    It holds a charge and works fine. DOn’t know runtimne yet.

  24. Rated 5 out of 5

    Customer

    Exactly the right item, right price. Increased AH. Charged up nicely, and fixed my old UPS. Dunno why I waited so long to replace this.

  25. Rated 5 out of 5

    osprey

    The battery terminals were a bit narrower than my original OEM battery and therefore narrower than my connection leads, but the leads attached firmly and stayed in place. It is working fine.

  26. Rated 5 out of 5

    Roseann Thompson

    works great, does and was just what my husband wanted.

  27. Rated 5 out of 5

    Mark

    Good quality replacement extended the life of my UPS. Good value, good quality.

  28. Rated 5 out of 5

    tjester

    Fit perfectly

  29. Rated 5 out of 5

    kalohe guy

    Just what I needed for a battery that was atleast 5 yrs. old, I had no problem inserting new one into the case…

  30. Rated 5 out of 5

    Russell J Borchert

    great buy, would buy again

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Excellent
Mighty Max Battery
Based on 3470 reviews
Battery arrived in a good shape package strait to my door steps
Arrived just in time to power my generator here in the cold Maine winters. Excellent service!
Arrived quickly from WALMART.COM. Perfect size and proper placement in my generator. Installation was easy. Generator fired right up. Battery came fully charged.
New battery. Ready for cold weather!
So far these Might Max batteries are good but it’s only the first day and they were on charge for 12 hrs. I’ll have to come back and do an update at some point in time. Ordered them on Amazon and got them the next day. I was encouraged by Mighty Max to make this google review and post pictures to extend my warranty for 3 months but there is no way to post pictures 🤣🤣🤣 It’s been a few months and I was able to go back and edit, so here is a video I made, the rest of the photos I have deleted. Batteries are still going strong. Update 12-11-2025
They arrived within 2 days of ordering them packaging was really good I haven't put them in my MX350 yet I hit them with my multi meter fresh out of the box and got 12.4v on both batteries so that is good
Fonctionne bien et s’est bien adaptée pour le remplacement de l’ancienne.
Battery arrived in perfect condition and 100% charge.
Strong battery! It spins my 24 hp Kohler engine super fast!
Arrived fully charged..great price