GT1 head or OPS head?
 

Hi all! I am going to buy a complete system of BMW GT1 and DIS from eBay. I searched in eBay and found there were two different types of diagnostic head for the system. One is called GT1 head (yellow color) and the other one is called OPS head (Orange color). Does anyone here know what the difference between these two heads? For my 2001 made E53 X5 4.4i, which head should I buy? One more thing, which cable shoud I buy for my X to use this system? OBD cable or 20 pin cable? Thanks for help with hands on gound!!!

heh, you'd need both unless you got V44. Gt1, afte V44 is only diagnostic, while if you wish to update, authorize or activate modules you need SSS, which is the orange OPS head. GT1 is the yellow head, V44 and before V44 will allow you to do both with this tool, but as it V44 is a bit old (Around 4 years now) what it can do will be limited compared to what a newer Gt1 DIS system can do, and a SSS system. If you're interested, I'm selling a Gt1 complete system for 1900$.