Description:These square nuts have a 4-sided, square design which provides a greater bearing surface when installing. Square nuts are designed for use with square-headed bolts, though they can also be used with some machine screws. The large surface provides better resistance to loosening. Also used with flat washers of compatible size and material.Specification:Material: Carbon steelGrade: 4.8Thread Size: M6 x 1mmEdge width:20mm/0.78"Height: 5mm/0.2"Package Content: 10 Pcs x Square Nuts.
eBay