For the UPPAbaby models, they are specific to the Vista and Cruz models of strollers. The ride-along Vista model is bigger than the other Vista model. For the Lascal models, one is a maxi and two are minis. The minis are more suitable for lightweight strollers or ones that are slimmer than regular strollers. These boards are smaller in size than regular boards. The weight limits for all of these boards are different too.