Makita power tool with a DeWalt battery? Milwaukee running on Makita 18V? Battery adapters for tools - YouTube
DeWalt Battery Adapter to Milwaukee – Power Tools Adapters
Amazon.com: DM18RL Battery Adapter for Dewalt for Milwaukee 20V/18V Li-Ion Battery Convert to for Ryobi 18V P108 ABP1801 Battery : Tools & Home Improvement
Milwaukee Nicad V18 to Dewalt DCB203 Lithium Battery Adapter
P0WER ELEKTR0 Battery Adapter for DeWalt DCA1820 18V-20V Converter with USB Port Function Compatible with DC9096 DC9180 Milwaukee M18 Battery to Dewalt 20V Tools: Amazon.co.uk: DIY & Tools