We can supply many kinds of butyl and natural tube in china. 3.50-4 Our certificate is ECE,DOT, ... /450-12, 155/165-13, 175/185-14, 175/185-15, 600/650-14, 7.00-14, 7.00-16, 7.50-16 ... /275-10, 250/275-17, 250/275-18, 275/300-14, 300-12, 300-16, 300-17, 300/325-17, 300 ... , 130/60-13, 130/70-12, 120/70-12 etc. Butyl Tube 3.50-4