Looks like the Domestic Sankey...
Here's a great link. If you click on the KEG fittings on the page...it lists the beers that are common to the type of connector.
There are two types of Sankey Kegs... Domestic and European. The probe on the European extends below the bottom of the coupler even when it's retracted...where the domestic retracts far enough...you can actually sit the coupler on a flat surface.
Enjoy your new toy!
I've collected every type of connector except for the Hoff Stevens twin probe and the M- Type connector... It's handy to be able to go keg shopping and not have to worry too much about having the right connector.