SET OF STEEL-ALUMINUM RIVET NUTS M3-M10 BY YATO YT-36480. CYLINDRICAL FLANGE, KNURLED, THANKS TO WHICH IT ADHERES MORE TIGHTLY TO THE FASTENED ELEMENT. COMPOSITION: STEEL: M3- 25 PCS., M4-25 PCS., M5- 25 PCS., M6- 25 PCS., M8-25 PCS., M10-25 PCS. ALUMINUM: M3- 25 PCS., M4- 25 PCS., M5- 25 PCS., M6- 25 PCS., M8-25 PCS., M10-25 PCS. RIVET NUTS ALLOW YOU TO DRIVE A SCREW OR SCREW WITH METRIC THREAD INTO SHEET METAL OR OTHER MATERIALS WHERE IT IS NOT POSSIBLE TO MAKE A THREAD.