This polymer base plate replaces the stock one with this simple alternative. It does not have quick pull tabs like other models but is instead simply a colored alternative to the stock plate.
Marui Model 17s now come with colored frames and aftermarket colored slides are also available as well as colored expanded magwells. This option allows you to add a little color to the magazine as well.
Alternatively, some users have been known to use colored mag base plates to color code their magazines. That way they can load different kinds of ammo or gas pressures in different sets of magazines in their loadout and that way they can tell them appart at a glance by color coding the base plates.