1-1/4"-12 SLOTTED HEX NUTS, PLAIN [10/BX]

1-1/4"-12 SLOTTED HEX NUTS, PLAIN [10/BX]

Slotted hex nuts, or castle nuts, have a hex body and slots cut near the top like that of a medieval castle.  These are used in conjunction with other fasteners like a cotter pin.  The cotter pin gets placed through the slots of the castle nut then slides through the hole of the fastener like a hex bolt with drilled hole.