This standard covering Metric Hex Flange Head Bolts conforms in all essentials with the American National Standard, ANSI B18.2.3.4M-Metruc Hex Flange Screws. The hexagon widths on the heads of these bolts are one size smaller for the respective bolt size than that of Metric Hex Bolts. These bolts are intended for general use in applications requiring a large bearing contact area; such as, where the bolt head is to bear directly on the mating surface over slotted or oversize clearance holes or against materials of relatively low compressive strength, or where other considerations might normally necessitate the use of a flat washer under the head of a metric hex bolt.