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Milwaukee M12 REDLITHIUM 2.0Ah Battery (2-Pack) & Charger Kit vs Milwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)

Head-to-head spec comparison to help you pick the right battery for your needs.

Milwaukee

$59.89

Buy on Amazon
vs

Milwaukee

$67.99

Buy on Amazon
Deciding between a genuine pack and a cheaper aftermarket one? Read our honest genuine vs aftermarket batteries guide.Read the guide →

Spec Winner

Milwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)

Wins on 2 of 3 spec categories

Spec-by-Spec Comparison

SpecMilwaukee M12 REDLITHIUM 2.0Ah Battery (2-Pack) & Charger KitMilwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)
PlatformM12M18
Voltage12V MAX18V
Capacity2 Ah5 Ah
Typecompacthigh-output
Genuine OEMYesYes
Fuel GaugeNoNo
Warranty5 years5 years
Price$59.89$67.99
Rating8.5/108.8/10
Buy on AmazonBuy on Amazon

Pros & Cons

Milwaukee M12 REDLITHIUM 2.0Ah Battery (2-Pack) & Charger Kit

Pros

  • Genuine Milwaukee M12 packs backed by Milwaukee's 5-year warranty
  • Kit includes two batteries plus a charger — a solid starter bundle for the M12 platform
  • Compact 2.0Ah cells keep M12 tools light for one-handed work
  • Straightforward drop-in fit for any M12 tool

Cons

  • 2.0Ah per pack is on the lower end for longer-runtime jobs
  • Only compatible with M12 tools, not M18
  • No fuel gauge on these compact cells

Milwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)

Pros

  • Genuine Milwaukee M18 pack backed by Milwaukee's 5-year warranty
  • Drops straight into any M18 tool — no adapters, no guesswork
  • 5.0Ah capacity gives solid runtime for daily-use M18 tools
  • REDLITHIUM cell design is Milwaukee's own in-house spec

Cons

  • No onboard fuel gauge — can't check remaining charge at a glance
  • Costs more than aftermarket M18-compatible packs
  • Only fits the M18 platform, not M12 or other brands

Our Verdicts

Milwaukee M12 REDLITHIUM 2.0Ah Battery (2-Pack) & Charger Kit

A genuine Milwaukee M12 two-battery-and-charger kit is the straightforward, warranty-backed way to get started or restock on the M12 platform — not the highest capacity, but the safest default.

Milwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)

A genuine Milwaukee M18 pack is the safe first buy for anyone standardized on the M18 platform — real Milwaukee chemistry and the full manufacturer warranty, not a third-party guess.

Milwaukee M12 REDLITHIUM 2.0Ah Battery (2-Pack) & Charger Kit

$59.89

Buy on Amazon

Milwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)

$67.99

Buy on Amazon

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