Indexing mechanism for multiple-station, glassware inspection machines in which two or more pocketed star wheels are used. The mounting of the plural star wheels, which are selected as to size of pockets depending on the height and width of the ware being inspected, is simplified by the use of a universal hub to which the lower star wheel is fixed. Additional star wheels are mounted on the hub at adjustable heights by the use of split, clamping rings that are keyed to the hub to maintain vertical orientation of the pockets of all star wheels.