This is a universal cotter pin. It is used to hold the inner brake pad on the front brake caliper on the Honda CB450/750K models. It was also used in other places on many other models.
Replaces Honda Part Number: 94201-16120
Fits Honda: (used to attach inner front brake pad to caliper B)
CB450K Super Sport - 1970-1971
CB750K Four - 1969-1976
and many more...