Product Details:Material: BrassFemale Thread Diameter: M3Total Length: 4mm/ 0.16"Outer Diameter: 5mm/ 0.2"Package Content: 120pcs x Knurled Insert NutsMaterial The knurled thread insert nut is made of brass which is not easy to rust is anticorrosion easy to conduct heat and has good conductivity. It makes the nut can be heated quickly and inserted easily greatly reducing your working time.Feature Twill knurling design has better pullout and torque resistance so that it will not easy to fall off and is easy to fix. The embedding nut has a guide valve so there is no need for a counterbore or countersink.