This book has a slim shape and is designed to fit in most mandolin cases. The chords are group according to keys. For example all the chords in the key of C are grouped together. I found this a very useful and easy way of arranging chords.
Sometimes a different chord shape would be shown for the same chord in different keys. This could be a bit confusing however it is always good to know different chord shapes!
Overall I would say that is an excellent reference book for chords. It is handy that it fits in your mandolin case. It can always be used as a quick reference in sessions.