Section 17 VEHICLES, AIRCRAFT, VESSELS AND ASSOCIATED TRANSPORT EQUIPMENT 87 VEHICLES OTHER THAN RAILWAY OR TRAMWAY ROLLING-STOCK, AND PARTS AND ACCESSORIES THEREOF 87 08 PARTS AND ACCESSORIES OF THE MOTOR VEHICLES OF HEADING 87.01 TO 87.05 87 08 99 COMPRESSED NATURAL GAS (CNG) SYSTEMS Commodity Code Description 87 08 99 30 COMPRESSED NATURAL GAS (CNG) SYSTEMS 87 08 99 40 OTHER PARTS AND ACCESSORIES, FOR TRACTORS 87 08 99 90 OTHER PARTS & ACCESSORIES FOR M/VEHICLES OF HD 87.02-87.05