These cases are designed to fit in a breast pocket of a jacket, but are equally useful in any number of ways. As pictured, they can be used with or without secondary pen sleeves.
I have personally used these for a number of years, holding four Rickshaw (or similar) pen sleeves in a case, and can attest to great durability. The design allows the top flap to be pulled over the pens to keep them secure inside the case.
Additionally, the case is designed to transform into a standup pen holder when the pens are in use.
