DEWALT 18V to 20V MAX Lithium-Ion Battery Adapter, Charger, (2) 2.0Ah Battery Packs and 20V MAX XR 5.0Ah Battery DCA2203CWDCB205 - The Home Depot
DEWALT 20V MAX Lithium-Ion Battery Adapter for 18V Tools DCA1820 - The Home Depot
JESTOP V8 Battery Adapter for Dewalt 20V Lithium Battery Converted to Replace for Dyson V8 Battery, Works with Dyson V8 Series Animal Absolute Vacuum Cleaner (DW20V8 Adapter ONLY) - Walmart.com
DEWALT 18-Volt 2-Amp Hours Power Tool Battery at Lowes.com