5pcs M8x1.25mm 304 Stainless Steel Hexagon Slotted Castle Nut Silver Tone

M8?thread diameter, 1.25mm pitch, GB6178 bolts.
A hex nut with opposed slots cut into the top of the nut through the centers of the flats. The slots are on the end ?opposite the bearing surface.
The slots are for the insertion of a cotter pin to secure the nut when used with a drilled shank fastener.
Commonly used in the automotive industry to secure front wheel bearings or wheel hubs to spindles on cars and ?trucks.