The terminal adapter board provides a professional look and feel and enables secure connections to sensors, motor drivers and servos. Use this dock to add extra connections to your Nano. It uses screw terminals so that you can be sure the connection is strong, and also allows you to use thicker wires.
The terminal adapter is for the Arduino Nano V3.0 but can also be used for the earlier version. (You just have to remember that pins A0 - A7 are in the reverse order)