Yes if they are new in box they will come with a second plate, or one plate with a bunch of holes to work in the 4x4 bolt pattern. It they are used they might not come with the correct mounting plate, but you can get them.
The disk on the custom is a uni disk so it will work on everytthing... YOu only get one pair of discs with the Custom the Uni disk!! works on Burton boards and 4x4 mounting systems