It plugs in to the factory harness for the security gateway module. Your OBD2 port stays open. Also acts as a SGW bypass if you wa t to use alfaOBD. There are lots of other features it provides that you may find useful. I love mine, and feel it was worth the price. You can find them on group buys for $50 off several times a year.Jesus f*cking christ that is expensive.. i'm assuming that the Tazer module just plugs and stays in your OBD port indefinitely??