Four-slot slotted round lock nut has four outer slots for hook spanner installation. Normally matched with lock washer; bend the washer tab into slot to achieve anti-loosening function.

It is used for axial positioning of shafts and locking inner rings of rolling bearings. Materials: 45# carbon steel, A2(304)/A4(316) stainless steel. Surface finish: black oxide, blue-white zinc, yellow zinc. Widely used for gearboxes, machine spindles, rollers, construction machinery and bearing fixing.