Products word： 　The brake rotors and drums are made from Grey Iron G3500. As for brake rotors, we could provide solid (type S), vented (type V), rotor with HUB and Bearings (type H) and H type rotors with ABS Ring. 　our products are sorted into 3 groups. 　First are rotors of type S, V and drums applying to passenger cars in the markets of North America, Japan, Middle East and South Africa. 　Second are rotors and drums applying to heavy trucks in West European market. 　The third one are specially designed for racing vehicles and to be exported directly to OEM markets. 　All above mentioned products have enough strength and hardness so that no deformation during use. Beside that advantage our products are durable and smooth when running. With heat-conducting fins on the surface, brake drums are easy to be cooled. -------------------------------------------------------------------------------- Technical Standard: 1 Material Specification Based on the related items of China Standard GB9439-88 and referring to ASTM, Material Specification conformed to the following conditions: 1-1.American Standard G3500 1-2.Microstructure: Matrix Pearite ≥ 95% 　　Graphite Size: grade 4 to 5 　　Quantity of A Type Graphite ≥ 85% 　　A Type Graphite spaced evenly 1-3.Chemical Composition C: 3.0%-3.3% Si: 1.8%-2.2% Mn: 0.6%-0.9% S: ≤ 0.12% P: ≤ 0.15% Cu: 0.2%-0.4% Cr: 0.15%-0.25% 2. Casting 2-1 Dimension tolerance unless otherwise specified according to GB6414 Grade 10. 2-2 No casting fins, air blisters, edges and sands allowed on the casting blank. For 　　vented brake rotors, the width of cooling channel should be even in circle and the 　　difference in thickness of two discs should be within ?.7mm. 2-3 Tested on braking surface, the Hardness is between HB187 and HB241. 3. Finished Products 3-1 No casting defects remain on the products. 3-2 Remove all sharp edges and burrs completely. 3-3 Thickness tolerance between two brake surfaces is ?.127mm. 3-4 The flatness of each brake surfaces are not more than 0.04mm, the parallelism is 　　within 0.06mm, Side-Runout of outer edge is less than 0.127mm. 3-5 Thickness variation between two brake surfaces at the same circle should not exceed 　　 0.0127mm. 3-6 Products should be balanced. The unbalanced datum is 216g.穋m MAX. 4. Packing 　　With a film of rust preventive oil, each rotor is packed by a plastic bag and a white 　　box, and then palletized. Product Introduction