It consist of an interface and a software for PC
The name is VCDS former Vag-Com
This is an american system and it's the original, not a chinese copy
The software has free upgrades forever.
This system can analyse every computer unit on the car.
You can read and erase fault codes, read data, reset service indikators, reprogram units
Read more here about it, see website link.
I, that sell this, has been the distributer in Sweden in 13 years for this.
This interface can be used on every car from 1990 until about 2004. It can NOT be used on cars with CAN bus!
Can be used with english ans swedish program
This interface is second hand, I give three months warranty
Three months free support included. If you need longer support, I can give for a small amount