Will this fit my existing M12 tools?

Yes. It is compatible with all Milwaukee M12 cordless tools and instruments, and charges on M12 chargers.

How does it compare with the compact 2.0Ah M12 battery?

It stores twice the charge, 4.0Ah versus 2.0Ah, so it runs longer. It is also larger and heavier, which matters on small tools.

Does cold weather affect it?

Milwaukee rates it to deliver fade-free power in sub-zero temperatures, and owners back that up on outdoor work.

Two M12 REDLITHIUM XC 4.0Ah battery packs, model 48-11-2440. Tools and charger are not included.

How long does it take to recharge?

About 60 to 77 minutes on an M12 charger, depending on the charger model.

Is it worth it over a cheaper 12-volt pack?

If you run M12 tools hard or work in the cold, the extra runtime and protection circuitry justify it. For light, occasional use a compact pack is enough.

Where is the Milwaukee M12 REDLITHIUM XC4.0 Battery cheapest?

At Acme Tools, for $79.00, as of our latest check.

What do buyers say about the Milwaukee M12 REDLITHIUM XC4.0 Battery?

Rated 4.4 out of 5 from 89 ratings.

Where can I buy the Milwaukee M12 REDLITHIUM XC4.0 Battery?

13 stores we checked sell it, including Acme Tools, Burns Power Tools, Grainger Industrial Supply, Home Depot, MSC Industrial Supply.

Milwaukee M12 REDLITHIUM XC4.0 Battery Price History: Lowest $79.00

What reviewers say

4.4 / 589 ratings

Owners rate the XC4.0 highly for runtime and cold-weather reliability, and many say it outlasts the compact packs on the same tools. The main complaints are weight and the price of buying in pairs.

What people mention

RuntimePraisedOwners say a charge lasts far longer than the compact 2.0Ah packs on the same tools.
Cold weatherPraisedUsers report steady power in freezing conditions where other packs fade.
WeightCriticisedSome find the extended pack makes small M12 tools noticeably heavier and top-heavy.
DurabilityPraisedLong-term owners report the packs survive years of jobsite use.
ValueMixedBuyers like the capacity but question paying for two packs at once.

From Acme Tools

All-weather performance: delivers fade-free power in extreme jobsite conditions
Best-in-class construction for long-lasting performance and durability
REDLINK Intelligence optimizes performance and provides overload protection through total system communication between tool, battery and charger
Powers most Milwaukee M12 cordless power tools
Recharges in 60-77 minutes
4Ah (48 watt-hours) of runtime, even in sub-zero temperatures

Materials: 12-volt lithium-ion
Fit: Compatible with all Milwaukee M12 cordless tools and instruments
Guarantee: 3-year limited warranty
Shipping: Free FedEx/UPS small package Ground shipping and free ABF/YRC freight ground shipping on most orders within the 48 contiguous states; in-stock expedited orders
Packs: Two pack
In the box: (2) M12 REDLITHIUM XC 4.0Ah Battery Pack (48-11-2440)

About the Milwaukee M12 REDLITHIUM XC4.0 Battery

The Milwaukee M12 REDLITHIUM XC 4.0Ah is a 12-volt lithium-ion battery pack with extended capacity. It provides 4Ah (48 watt-hours) of runtime, including in sub-zero temperatures. It is compatible with Milwaukee M12 cordless tools and instruments.

REDLINK circuitry protects against overloads and cell-damaging discharge. REDLINK Intelligence lets the tool, battery and charger communicate to optimize performance. Cell monitoring and temperature regulation extend the battery's operation and life expectancy.

The battery is built for all-weather performance and delivers fade-free power in extreme jobsite conditions. It recharges in 60 to 77 minutes.