These PC screw are made of carbon steel which is rustproof, anti-aging ,strong and lightweight.rustproof, anti-aging ,strong and lightweight.[Widely Application]: These screws are suitable for all universal computer construction or repair.For motherboard,PC casing, supply, hard drives, fans and fixed installation of floppy disks/CD-ROM/DVD-ROM drives.Perfect for PC case, supply, motherboard, hard drives, fan and floppy/CD-ROM/DVD-ROM drives fixed installation, they are placed in a box, easy to find and Colour:As shownMaterial:metalPackage Contents:6 x Chassis hand screws (.5 x 6, Silver)6 x Chassis hand screw (.5 x 6, black )30 x Conventional chassis fan screw (M5 x 10, Silver)30 x Conventional chassis fans hold screw (M5 x 10, black)24 x Chassis high-strength screw (.5 x 6)40 x Hard drive screws (.5 x 5)40 x Motherboard fixed screws ( x 5)40 x CD-ROM screws ( x 4)24 x Motherboard conventional copper column ( x 6 + 6)40 x Circuit board insulation washer ( x 8, red)Only the above package content, other products are not included.Note: Light and different displays may the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.