You are only buying the highlighted element, and not a complete set of a Penarosa watch
This watch-element is interchangeable and compatible with all of our other elements.
By adding this interchangeable watch-element to your collection, you can enjoy more versatility of your Penarosa watch. The swapping of any of the four Interchangeable elements can be done easily, anytime, anywhere and without the use of any tools.
See Users Manual