Black and Decker 20V to Milwaukee 12V Battery Adapter

Use your Black and Decker 20V batteries on Milwaukee M12 cordless tools, without buying into a second battery platform. Your Black and Decker 20V battery is 20V where Milwaukee M12 tools expect 12V. A DC-DC converter inside steps it down and holds it there, so the tool never sees more than it is built for. The molded ABS housing keeps it light and hard-wearing, and pure copper contacts keep current delivery steady. One battery platform across more tools means less spent on batteries and less to keep charged. It also carries battery protection electronics (BMS) inside.

Specifications

• SKU PTA-BLA20-MIL12
• Fits this battery Black and Decker 20V (Lithium-Ion)
• Battery voltage 20V
• Runs these tools Milwaukee M12 (Lithium-Ion)
• Tool voltage 12V
• Housing ABS (Injected)
• DC-DC converter Yes — 20V to 12V
• Terminals Copper
• Current rating 40A continuous (80A peak at 18VDC for up to 2 seconds)432 Watt continuous at 10.8V nominal
• Weight 135 g (4.8 oz / 0.3 lb)
• Dimensions (L × W × H) How It's Measured 110 × 70 × 113 mm (4.33 × 2.76 × 4.45 in)
• Colour Black, Red
• Operating humidity 5–95% RH
• Operating temperature -10 °C to 50 °C (14 °F to 122 °F)
• USB port No
• Built-in BMS protection Yes
• What's in the box Battery Adapter
• Warranty 12 months after the date of delivery
• Revision Revision 01 (released on August 11, 2026)

Why choose this adapter

• A Battery Management System inside the adapter cuts power before the battery is drained too far — protection your battery may not have on its own.
• Injection-moulded ABS, not 3D printed — no layer lines to split under load.
• Solid copper terminals, so less of the current is lost as heat.
• Rated for 40A continuous with 80A peak at 18VDC for up to 2 seconds, so a high-draw tool is not held back by the adapter.
• Covered by a 12-month warranty from the day it arrives.

Black and Decker 20V and Milwaukee M12 compatibility

It works in one direction only: Black and Decker batteries powering Milwaukee tools. For the opposite pairing, see adapters that run on Milwaukee M12 batteries.

Compatibility can vary with the exact battery and tool model. Before ordering, confirm that your battery belongs to the Black and Decker 20V platform and that your tool takes Milwaukee M12 batteries.

Important charging and safety information

This adapter is for powering cordless tools and nothing else. It cannot charge Black and Decker or Milwaukee batteries and must never be connected to a charger of any kind. Always take the battery out of the adapter before charging, and charge it on the original charger made for your Black and Decker 20V battery.