20pcs Flat Head Metric Steel M5 Blind Insert Rivet Nut;

WHAT IS A Rivet Nut?
A Rivet Nut 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 Rivet Nut fastener. The added benefit of not only being a dependable fastener, they are ready to use with clean threads available for screw attachments.Blind thinsheet materials that are too thin for a tapped thread. Blind Rivet Nuts also areused when an application has little or no access to the backside as they can be installed from the front side of the work piece.