A fastener is a tubular rivet with internal threads,It can be installed in seconds form one side of the work. Once installed, no finishing work is required on the fastener. The added advantage of not only being a dependable fastener, they are ready to use with clean threads available for screw attachments,Blind thin sheet materials that are too thin for a tapped thread. Blind Rivet Nuts also are used when an application has little or no access to the backside as they can be installed from the front side of the work piece. Product Name: Rivet Nut; Material: Metric Steel, Zinc Type：M5 Thread Diameter: 10mm; Total Length: 21mm Grip Range: 1.0-5.0mm; Body Diameter: 12.9mm Application hole size: 13mm; Weight: 332g Package Content: 40 x Rivet Nut Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.