Review on DEWALT 18V 20V Adapter DCA1820 by Jeffrey Gallagher

Adapter works great with any MAX 20V battery and most 18V tools. And it works with any 18V too Tool, as long as you modify the adapter (note that this will void your warranty), but it's only a $50 adapter. There are notches sticking out on both sides of the adapter that need to be cut or sanded, see my photo. I used my bench grinder, it takes less than 20 seconds to complete the job. After modification, it will fit any 18 volt tool. Please note that since all Dewalt 18v tools are actually 20v powered, there is nothing wrong with using it with one of the Dewalt 18v tools. The only tool I have won't work properly . So this is my 18 volt nail gun that turns on. The amber light indicates low voltage when using this adapter (and I thought the new battery had a higher voltage than the old 18v battery). All my other Dewalt 18v tools will work with my modified adapter and I have almost all tools that are 18v. One major downside is that this will drain your 20v MAX battery if you leave it plugged into the adapter. I have 4 of these DCA 1820 adapters and they all show resistance when an ohmmeter is used across the terminals. I left the 20 volt battery fully charged on all 4 adapters for a couple of days and they all gave me 2 lights during that 2 day period (indicating the battery was almost dead). A 20v battery of tools during storage (so the batteries don't run out) so I gave it 4 stars but overall it's a good way to use new batteries with old tools.