Cheap And Discounts 10Pcs/lot Aluminum Flange Lock Nut M2 M2.5 M3 M4 M5 M6 Aluminum Nylon Hex Insert Lock Nut Locknuts self-locking Nut Wholesale. Buy Directly From Merchant JINGRUI Hardware. Enjoy ✓Free Shipping Worldwide! ✓90 Days Buyer Protection. ✓Easy Return. ✓Money Back Guarantee.