7/16"-14 Serrated Flange Lock Nut - Plated 7/16"-14 serrated flange lock nut - plated SFN71614 $0.213/ea
3/8"-16 Serrated Flange Lock Nut - Plated 3/8"-16 serrated flange lock nut - plated SFN3816 $0.084/ea