BatteryGuy > 12 Volt 21 Ah SLA Batteries
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12 Volt 21 Ah SLA Batteries

12 Volt 21 Ah SLA Batteries in stock from $153.90. We have a full range of 12 Volt 21 Ah SLA batteries available for immediate delivery nationwide. Order online or call Toll Free.


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12 Volt
21 ah
252 Wh
L: 8.07"
H: 6.83"
W: 3.43"
15.50 lbs

Power-Sonic PS-AUX50 12 Volt 300 CCA Start-Stop Auxiliary SLA AGM battery. Our Power-Sonic PS-AUX50 is commonly used as back-up support to a vehicles main starter battery in start stop situations or when needed to deliver a constant power supply for the vehicles electrical system.  **NOTE: This is a AGM battery and does not require or have a vent hole to hook up a venting hose for cars with standard lead batteries.  If your car does have a venting hose this battery will not work for your application and you need to find a standard lead battery that will accept this hose to avoid possible issues with the operation of your vehicle** NOTE - This does not work with the BMW I3 Vehicle**

(This is one Battery – Please verify quantity needed for your application before ordering)

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    • 5 out of 5:
    • "Arrived promptly, very happy with the transaction."
    • Steve I., December 29, 2021
    • 5 out of 5:
    • "Perfect transaction."
    • KEN, December 24, 2021
    • 5 out of 5:
    • "Ordered this battery for a very old high lumen spotlight....worked perfectly! We were ready to throw the light away but ordered this battery at last minute. The battery saved the light!"
    • minpin08, December 23, 2021
    • 5 out of 5:
    • "Great Seller who very promptly shipped 2-day Priority Mail to me. The post office picked up the item Nov 29 for 2-day delivery then finally got around to delivering it Dec 11! Bad post office."
    • Craig, December 11, 2021
    • 5 out of 5:
    • "great product"
    • DAN, November 30, 2021
    • 5 out of 5:
    • "The seller provided all pertinent Info in a timely manner."
    • J. Creasy, November 29, 2021
    • 5 out of 5:
    • "worked great."
    • Mel, November 22, 2021
    • 5 out of 5:
    • "Shipped same day - early arrival. Well packaged. Excellent product and service."
    • Penfield, November 18, 2021
    • 5 out of 5:
    • "Great experience buying from this retailer, item was shipped in a timely manner and was exactly as described."
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    • 5 out of 5:
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    • Jim S, November 12, 2021
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