Square nuts are four-sided nuts as opposed to the more common hex (six-sided) nuts.

The surface area on the flats is larger than hex nuts, which reduces wrench slippage. However, you cannot use hex drivers such as sockets and nut drivers.

Machine screw square nuts are available in smaller sizes and also smaller in width and thickness than regular square nuts.

Machine screw square nuts have flat tops and bottoms—the edges and corners are not chamfered (beveled).

Regular square nuts have a flat bottom bearing surface and a crowned washer-faced top. Regular square nuts are often used with square bolts.

Size: M6/M8/M10/M12/M16/M20

Width across flats: as per size

Thickness: as per size

Thread type: metric corse/fine right-hand thread

                    imperial thread is available upon request

                    left-hand thread is available upon request

Material: steel

Grade: 4.8/6.8/8.8/10.9/12.9

Finish: plain/black oxide/zinc plated (galvanized)/hot dip galvanized (HDG)

          other kinds of surface treatment are upon request

Technical info: DIN 557