As mentioned before, it is explained in the New Member Intro thread and it describes "trim level" as well as listing out the options. Yes, for those that wish to remind new member to put it in their siggy, saying Model and/or describing what a trim level is will help them to understand what you are asking.
In a perfect world, folks would read up on the sticky'* and notices, thereby learning all that they need to know. But it'* not a perfect world...
Have patience, my dear friends, have patience.
The East Coast Mom