Everyday Innovations Booksling Mini Pen Holder, Colors May Vary
The BookSling Mini is a high quality black elastic strap that holds a pen (included!) to your small journal, reading book, address book and sketch book.  You can even wrap the strap around a deck of index cards to keep them together in your backpack or purse!  A mini blue pen is included (black ink).  Fits all pocket Moleskine notebooks.