... .Four-high rolling mill 2.long life 3.the best price 4.high quality Specification Type: 820, 750, 650, 600, 520, 450 Max Rolling Power ... Supporting Roll Max. Rolling Diameter (mm): 700, 700, 660, 520, 520, 480 Min. Rolling Diameter (mm): 650, 650, 610, 480, 480 ... , 420 Rolling Diameter (mm): 800, 720, 630, 600, 520, 430. Four-High Rolling Mill