Coltri BOOSTER COMPACT third stage "red head" valve kit. Does not include "red head." For compressors manufactured 03/2014 and later. Also fits MCH5 CNG and MCH10-MCH14 CNG manufactured on or after 03-2014. Described in Coltri literature as "Service Kit 3rd Stage Valves G3." For additional information on this kit, see page 10 of Booster Compact Parts List, page 20 of MCH10-MCH14 CNG, or page 18 of the MCH5 CNG Parts List; all located under the User Manual tab.