Castle Nut 1/2 x 13 UNC Black High Type Gr.8

Castle Nut
Hexagon High Type
Imperial UNC
Black / Self Color
High Tensile Grade 8
Dia: 1/2'
TPI: 13
DIN: 935
Wrench Size Across Flats: 3/4'
A DIN 935 castle nut (or castellated nut) is a specialized hex nut featuring a notched, cylindrical top that resembles a medieval castle's battlements. It is designed to create a "positive locking" connection that is virtually impossible to loosen accidentally. An split pin is normally used with the nut.