The Dewalt DCA1820 enables new Dewalt XR batteries to be used with older Dewalt XRP machines, this means that you do not need to replace your older Dewalt power tools and can use newer technology batteries on the older machines. Some newer Dewalt batteries have extended runtime and are much lighter, the Dewalt XR 5AH battery is roughly the same size and weight as an older Dewalt 2AH XRP battery. In other parts of the world the Dewalt DCA1820 is sold as the 18v to 20v battery adaptor.
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