OBD2 Breakout Box Special breakout box which enables you to access all pins on a 16 pin OBD2 connector via 4mm female banana sockets Some cars use a lot of different K-lines for it' s different systems like engine ECU, ABS, etc. this is needed for most scantools if you want to access all the systems just by pluging the K-line into the right socket of the system ( Examples of such cars are Opel or Mercedes Benz)