Before the introduction of indexed shifting, the width of a five-speed or compact six freewheel was approximately 32 mm; the introduction of indexed shifting supposedly made standardized sprocket spacing necessary. Shimano and Campagnolo both came up with independent standards, and SRAM later followed Shimano's lead in respect to sprocket spacing and cassette width. The width of early Shimano six- and seven-speed cassettes was 36 mm, and early eight-speed 40 mm wide. Shimano then changed again and standardised eight-eleven speed cassettes on 41.5 mm and second generation seven-speed to 38 mm. The widening of the sprocket carrier on the cassette hubs to 41.5 mm resulted in a decrease in the distance between the hub flanges.