The Turbo 4Lane Timer, Custom Carrying Case, Your choice of Software, and a builtin USB port with USB cable.

Separately these would cost you $424, so you save $35!

Be sure to choose your lane spacing (3.25", 3.5", 3.75" or 4.0") and your choice of software.

The difference between the DerbyPak 1 and the DerbyPak 2 is whether you are using a USB port or a Serial port.