This keypad is arranged as 3 columns of 4 rows each, and has a 7-pin male header with 0.1-inch spacing on the back. It can be plugged directly into a solderless breadboard or used with a ribbon cable (e.g. our RC14FF16). The currently stocked version of this keypad is black with white buttons.
A datasheet is available here: http://support.technologicalarts.com/docs/Components/MK3X4specs.pdf