Stevenspdo

I drive an A6 Allroad 2016 model.  3.0 TDI V6 Quattro. It has a place where you can insert a dipstick and I want to purchase one so I am able to physically see the oil.  Can somebody please tell me the dimensions of the dipstick I would need?

many thanks. 

I am about do my nut so if there is any advice out there, then I would be most grateful.  I have purchased an O2 sim for the car.  The Sim inserted and recognised by the car.  The Sim is shown online and I have ticked the "data roaming" box. However when I look at the "connection status" screen, it reads  "data roaming inactive". How do i sort this?