This pack of Pozidriv double countersunk head wood screws are constructed from a durable carbon steel. They're ideal for a range of DIY applications. Comes with 12 different single thread wood screw sizes: 50 x 4.0x40mm 40 x 4.0x20mm 50 x 4.0x30mm 20 x 5.0x70mm 40 x 4.0x30mm 70 x 3.5x30mm 80 x 3.0x25mm 20 x 5.0x60mm 50 x 3.5x50mm 80 x 3.5x20 80 x 3.0x16mm and 20 x 5.0x50mm.