The SparkFun Inventor's Kit Bridge Pack - v4.0 was designed to provide you with an easy way to move into the next SIK edition without buying a whole new kit. Each Bridge Pack includes all of the new parts found in the SIK v4.0 that aren’t in any of the version 3 kits, as well as the most up-to-date, spiral-bound guidebook so you can get started right away!