Air dryer parts used for truck trailer,heavy-duty truck 1:UNL: ... ,22=M12, (22+4=M12 Detailed description of Air dryerAir dryer parts used for truck trailer,heavy-duty trucksuch as MAN ... Point can upto -40 centigrade 5.Environment-friendly6.compressed air dryer benefits 7.sing-chip system control 8.certified with ISO9001 ... and competitive price.OEM and ODM orders are welcome ! Air dryer parts