The object of this little book is to provide key collectors with a quick reference guide to most of the know key types. As many as possible of the key types developed over the past one hundred and fifty years are illustrated. ~ From the Foreword
This is intended to be a quick reference guide to the types of keys manufactured in the 19th and 20th centuries and it does exactly that. This is probably the most information I have ever seen in a book this size. For more indepth guides there are Standard Guide to Key Collecting and Paracentric Guide to Key Collecting.