Amazon.com: for Dewalt 20V to 18V Battery Adapter, JJXNDO 2-Pack DM18D Upgraded Version DCA1820 Converter for Dewalt 18V/20V & for Milwaukee M18 18V Battery to Work for Dewalt 18V Nicad & NiMh
AEG 18v battery adaptor to Dewalt XR tools – Your ToolBox
Dewalt 18v XR battery adapter / converter to Hitachi /Hikoki tools, One Piece | eBay