Unique Bargains M2x0.4mm Hex Lock Nuts Stainless Steel Nylon Insert Self-Lock nuts, 20Pcs Silver

1.Nylon-insert lock nut, polymer-insert lock nut, or elastic stop nut, is a kind of locknut.
2.It is a nut with a nylon insert that resists turning.
3.The plastic insert is placed at the end of the nut, and its inner diameter (ID) is slightly smaller than the diameter of the screw.
4.The insert elastically over the threads of the screw, but threads are not cut into the nylon.