Genuine registered ROSS-TECH HEX-USB+CAN. Unlimited VIN. Owned since new, Purchase from NHN in AUG 2012. Selling as it doesn't work on my new A4. £250 Posted, Bank Transfer or Paypal (Buyer Pays Fees)
The A4 has newer modules that the interface cannot decode. Don’t know about your TT, you could ask in the VCDS section or check ROSS-TECH site. It worked on on my 2017 A3.