The phrase "appearance package" refers to a set of enhancements or upgrades made to the way something looks. It might include changes to the design, color, or style of an object to make it appear more attractive or unique. Full definition
There are new appearance packages for all models, as well as a new wireless Internet connectivity system. (automobilemag.com)
This new appearances package adds a sportier look to the vehicle, and while there's no performance upgrade, it's made to look like you have one. (glenbrookdodgechryslerjeep.com)