"Specification levels" refer to different levels or grades of detailed information or requirements provided in a specification document. Full definition
Standard specification levels include a power liftgate and keyless entry with a number of packages available to enhance safety, luxury and handling levels. (carbuzz.com)
It is very spacious though and the base specification levels include power leather seats an active exhaust system and rear park assist. (carbuzz.com)
Basic specification levels are good although you do pay a premium over the mechanically equivalent A6. (carbuzz.com)