DC coax connectors are typically found on wall-plug-in power supplies and power adapters. They are usually classified by the diameter of the center pin. 2.1mm and 2.5mm are the most popular, followed by 1.7mm and 1.3mm. All Electronics has a large selection of male and female DC power coax connectors as well as a selection of adapters that are very handy for changing the plug size if the power supply doesn't come equipped with the one you are looking for.
