Muzata 100Pcs Zinc Plated Carbon Steel Rivet Nut, Threaded Insert Nutsert Included M3 M4 M5 M6 M8 Splined Body:The Ribbed body provides increased torque-to-turn resistance over conventional non-Ribbed Rivet Nut. Lead-In Chamfer:The chamfer on the nut body makes the nut easier insert into the work piece. Large Flange:Has a large bearing surface it helps improve push-out Ability. Wide Grip Range:Material thickness ranging from (0,5mm) to (6.5mm). High-StrengthThreads:Nuts have a work-hardened surface providing high-strength, load-bearing threads.