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Braille Battery

Braille Lightweight 21lb AMG Battery (B3121)

Regular price $229.99 USD
Regular price $249.99 USD Sale price $229.99 USD
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Braille Lightweight 21lb AMG Battery

At 21 pounds, the B3121 is our lightest do eveything battery yet. Using our Advanced AGM racing technology we have put a lot of power into a very small package. With 1380 pulse cranking amps this has enough power to start more than any other battery in its weight class. This is the perfect model for those who want to shave half the weight of a standard Group 34 battery and still have enough power to crank over a steet car with V8 engine & standard compression. Used in everything from large Harley Davidsons to Hot Rods, road race cars, Corvettes & Vipers. (Note: while high in cranking amps, make sure battery has enough capacity for the vehicle intended to be used in.  Not designed for big block, high compression motors, those with no alternator, etc. where a full-size battery with high capacity is required.)  

   Physical Specs
BCI Group All Sizes Width 5.2" / 132mm

21lbs / 9.5kg
Height 6.8" / 173mm

6.6" / 168mm
Polarity Right Side Positive


   Performance Specs

Full Voltage Charge  13.2
Pulse Cranking Amps (PCA) 1380 Amp Hour (AH)  31
Reserve Capacity 1hr 15 mins

Life Cycle (10%DOD)  3100


Other Braille Battery & Accessory Products available for any chassis/engine - if you dont see what you’re looking for please message us directly.  

We shop our competition - if you find a lower comprable price we will match or beat it - message for details!

Braille Battery specializes in ultra-lightweight Lithium-Ion high performance batteries, and also distributes and sells the world’s first and only AGM carbon fiber race batteries. Within their product line you will find a large number of shapes and sizes to accommodate all racing needs, as well as a number of different mounting kits, chargers and battery trays. 

PROPOSITION 65 WARNING: These products may contain chemicals known to the State of California to cause birth defects or other reproductive harm. For more information visit