Dear Sir or Madam,We, shandong aona chemical co.,ltd. mainly produce carbon black( dry process with powder form ) used for any rubber products .the grade is : n220,n330,.n550,n660, n375,n339 n774 and so on. our products has sold to about 30 country ,and we have established good relationship with our clients . so if you are interested in our products,please contact me without any hesitation. With best regards,sunny