The air dryer filter is used to dry and dryer the compressed air from the pump so that those impurities will not enter the vehicle's braking system, so as to maintain the sensitiveness and effectiveness of the braking system.Can be used Golden Dragon bus, Kinglong Bus, Foton Oman, SINOTRUK HOWO, Shaanxi heavy truck, Dongfeng Liuqi, and so on. The dryer is produced by XFY, our own brand and guaranteed for half a year.