Your release will be grouped into one of three categories based on how many tracks and the length of those tracks.
It’s important to note that this is not a customizable part of your release. For this reason, it is not necessary to list your intended product classification in the title or version title of the product.
For example, putting EP in your title and artwork without checking if the content of your release will classify as such may result in your product being queried and returned to you.
The iTunes Style Guide states the following in regards to product classification specifications:
An album must be identified as a single if it contains one to three songs that are less than 10 minutes each.
An album must be identified as an EP if it has:
One to three songs with one song at least 10 minutes long and a total running time of 30 minutes or less
Four to six songs with a total running time of 30 minutes or less