05B-3,06B-3,08B-3,10B-3,12B-3,16B-3,20B-3,24B-3,28B-3,32B-3,40B-3,48B-3,56B-3,64B-3,72B-3 3. Material: carbon steel 40 Mn stainless steel 4. All parts are heat treated (quenched and tempered) and controlled within a reasonable tolerance range. 5. Tensile strength: 15-20% higher than the standard 6. Quality certificate: ISO 9001: 2000, 7. Centerless grinding. 8. Good grease lubrication. Color: self, dark yellow, dark blue, black