This is a robot drive wheel we had made specifically for us. It does not have a bearing. It's 10 inches in diameter. 3" inches wide. Its Pneumatic with a 4 bolt pattern so you can easily mount it to a flanged hub.
This is a direct drive 4WD base Programmable robot kit that uses Nexus mecanum wheels. It is an Arduino robot platform for indoor robotics. It can vector in any direction. Includes a choice of Arduino for making a great Autonomous Robot.