Hercules 20V to Milwaukee 18V Battery Adapter
$39.89
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Hercules 20V to Milwaukee 18V Battery Adapter
$39.89
Use your Hercules 20V batteries on Milwaukee M18 cordless tools, without buying into a second battery platform. The molded ABS housing keeps it light and hard-wearing, and pure copper contacts keep current delivery steady. Fewer battery systems in the workshop, on the bench or in the van, and no extra chargers to find room for.
Specifications
- SKU PTA-HER20-MIL18
- Fits this battery Hercules 20V (Lithium-Ion) from Harbor Freight
- Battery voltage 20V
- Runs these tools Milwaukee M18 (Lithium-Ion)
- Tool voltage 18V
- Housing ABS (Injected)
- Terminals Copper
- Current rating 40A continuous (80A peak at 18VDC for up to 2 seconds)720 Watt continuous at 18V nominal
- Internal wiring 5 mm²
- Weight 127 g (4.5 oz / 0.28 lb)
- Colour Red, Yellow
- Operating humidity 5–95% RH
- Operating temperature -10 °C to 50 °C (14 °F to 122 °F)
- USB port No
- What's in the box Battery adapter
- Warranty 12 months after the date of delivery
- Revision Revision 01 (released on March 10, 2025)
Why choose this adapter
- 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.
- 5 mm² internal wiring, 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.
- Made for the Hercules 20V batteries sold at Harbor Freight, so the fit is the one you already own.
- Covered by a 12-month warranty from the day it arrives.
Hercules 20V and Milwaukee M18 compatibility
It works in one direction only: Hercules batteries powering Milwaukee tools. For the opposite pairing, see adapters that run on Milwaukee M18 batteries.
Compatibility can vary with the exact battery and tool model. Before ordering, confirm that your battery belongs to the Hercules 20V platform and that your tool takes Milwaukee M18 batteries.
Important charging and safety information
This adapter is for powering cordless tools and nothing else. It cannot charge Hercules 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 Hercules 20V battery.