The Marine Corps M1967 load carrying system – not to be confused with the Army’s M1967 gear - replaced the WWII designed M1941 system and consisted of a combat field pack, a cargo pack and a pair of suspenders. After testing by the 2nd Marine Division and Force Troops it was approved for issue in South East Asia, however, Marine Corps elements had begun to withdraw from Vietnam before the system could be issued.1
Though similar in appearance to the Army's M1967 nylon suspenders, the USMC model was considerably more sophisticated. The rear straps featured female snap fasteners that mated with the male snaps on the back of the combat pack and the padded shoulder straps boasted quick release buckles.
1.R&D News - Improving the load carrier by Maj. Sabater, Jr. (Marine Corps Gazette October 1972)
What's New? by SSgt. Jim Elliott. (Leatherneck June 1971)