I initially designed this in the pursuit of a system of containers that locked together, but found that it was difficult to make such a design that did not take up so much space. Instead, I focused on making as tight a fit as possible, ultimately leading to the choice to add holes on the bottle to let air escape, preventing a vacuum fit. 

Personally, I think the best features of this model are how it covers the label, allowing for more discreet pill storage, and how it makes the pill bottles more stable, preventing accidentally knocking them over. 

These containers will fit CVS & Walgreens amber prescription bottles with a paper label. They did end up being modular, as they can nest quite well with themselves.