Barrel connectors come in a wide variety of widths and also pin sizes. For 12v, 5.5mm OD / 2.5mm ID is the
most common, although 2.0mm ID is also seen frequently. I found these nice barrel pigtails on Amazon. They
use a "fork" connector for the center pin, so work fairly well with both IDs. But the most interesting feature
is just how heavy the wire is in the cord. Usually, these cords have something like 20ga or thinner, but these
pigtails use 16ga, and it looks like pure copper too. They're perfect for low loss, higher current delivery.
