Features: The star locking washe is one of the indispensable accessories in most mechanical equipment, it have a variety of roles in fixing, supporting and damping. Make from 65 manganese steel materials which have good corrosion resistance, rusts resistance and excellent oxidation resistance, which can ensure long terms using. It use spring pressure to regulate reinforced shaped objects and is used to tighten and loosen threaded fittings. Widely used in machinery equipment, industrial production of shock absorption, can meet your different needs in daily. Total 9 size 360pcs in a box, different size can meet your different needs. Specifications: Materials: 65 manganese steel Diameter: 6mm (0.24inch)/8mm(0.31inch)/10mm(0.39inch)/12mm(0.47inch)/14mm(0.55inch)/16mm(0.63inch)/18mm(0.71inch)/20mm(0.79inch)/25mm(0.98inch) Package Includes: 50Pcs 2.5x8mm 50Pcs 3x10mm 40Pcs 4x12mm 40Pcs 5x14mm 40Pcs 6x16mm 40Pcs 8x18mm 30Pcs 10x20mm 50Pcs 2x6mm 20Pcs 12x25mm note: Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to difference between different monitors, the picture may not reflect the actual color.