what I have gathered from this thread.
1.) the DC female output on the unit is a "N" 5.5mm X 2.5mm
2.) The stock cable terminates in a "M" 5.5mm x 2.1mm
Ted and others. This is a bit off. I double checked the stock cable and its got the same connectors on both ends. These are not M connectors because I confirmed that a male M connector will not fit into the female jack on the battery. And earlier in this thread it was confirmed that the battery end of the cable has an N connector, so that means both ends of the cable have an N.
What I think must be going on is that since the hole in the N connector is slightly larger, the male N connector can work in a female M jack, but not vice versa.
That said, the tips that are included with the standard batch of tips includes an M tip, so nobody should have any problem with the stock cable and your dr680, which apparentnly uses an M.
Sounds to me based on what's being reported that 680 owners have the option of using either the stock cable with the n connector or adding the M tip onto the end of the stock cable.
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