This invention relates to a wrap-around carrier which is held together by a single locking system, which is a secondary locking system in which the secondary male locks are formed as an extension of an outer secondary locking flap with an inner bottom flap having a secondary female opening for each secondary male lock. Assistance in holding the secondary male locks in the vertical locked position between two containers in the carrier is provided by a female flap formed in the female opening in the inner bottom flap. Further assistance is provided in holding the secondary male locks in the vertical lock position between two containers by the containers having flexible side walls and carrying a liquid whose weight pushes out against the walls of the container and creates tension in the wrap-around carrier thereby holding the secondary male locks in the vertical locked position.