ISO certification Manufactures specialized in carbon Black in China,the specification of carbon balck N220 is below,for details of N330,N550,N660 kind pls contact sharon at chemliancheng dot com or msn hebeilianchengzhang at hotmail dot com.or call 86 311 87068688 Re: Carbon Black N220 Appearance: Black powder or granular Specification: Iodine Absorption Number (g/Kg) : 121+/-5 DBP Absorption number (10-5M3/Kg) : 114+/-5 DPB Absprption Value of compressing sample (10-5M3/Kg): 93-107 CATB Surface Area (103M2/Kg) : 106-116 Nitrogen Surface Area (103M2/Kg): 114-124 Tinting Strength : 110-120% Heating Loss: 3.0 max Ash : 0.5% max Tensile Strength: -0.8 MPa min Extension%: 10Min Map Modulus at 300%: -2.5+/-1.3 Packing: 25kg/bag, 16MT/ 20’FCL