US Patent 7213819 Gym scooter

A scooter includes a platform and at least three casters. The platform has a horizontal top surface and at least one vertical side surface extending downwardly from the top surface. The casters extend downwardly to support the platform when the platform rolls. The scooter also comprises a horizontal flange and a vertical flange. The horizontal flange extends away from the vertical side surface. The vertical flange extends from the horizontal flange. The vertical side surface, the horizontal flange and the vertical flange define a groove adapted to receive a mating tongue on a second scooter. This provides an integral, low-profile tongue-and-groove type of connection between two or more scooters.