Promo Pack Concept

This is a concept design that I made several years ago but I think it's interesting to show it here.
It's a promo pack for natural drinks that was going to be sold in the shops to a chain of gas stations. The promotion was "Buy two, get three" or as I decided to write "2=3" as a part of the design. The package had to be easy to storage, strong and to contain all the three bottles of 500ml each. So I thought of an option to use the "L" shaped design because it will save storage space, would be easier to transport and because of that it will save money for transportation.
The client wanted to be shown on the package all of drinks' flavors.