Flanged sintered bronze bearing Thrust side with built-in oil reservoir. This is our self-alignment feature. These bearing are meant to have some play in them. When you mount them, just use the shaft to rotate the bearing into proper position, or if it is not out of alignment by much, the bearing will correct its own alignment once it begins to rotate. If the bearings were not aligned properly and spinning at high RPMs then sure disaster would happen. Our self-alignment feature is a way to prevent this from happening. Product is manufactured in United states. This product meets customer requirement.