Amazon.com: JJXNDO for Dewalt 20V to 18V Battery Adapter, 2-Pack DM18D Upgraded Version DCA1820 Converter for Dewalt 18V/20V & for Milwaukee M18 18V Battery to Work for Dewalt 18V Nicad & NiMh
DEWALT 20 2-Pack 3 Amp-Hour; 3 Amp-Hour Lithium Battery in the Power Tool Batteries & Chargers department at Lowes.com
Amazon.com: EID for Dewalt 20V to 18V Battery Adapter, 2-Pack DM18D Upgraded Version DCA1820 Converter for Dewalt 18V/20V & for Milwaukee M18 18V Battery to Work for Dewalt 18V Nicad & NiMh