This is a hard cover edition of Jack Tods "Porcelain Insulators Guide Book For Collectors' The book was printed in 1971 and included are supplements A, B and C. A ton of info covers all phases of manufacturing to collecting.200 pages of reading that will make you a lot smarter than you were! The book shows a bit of wear but overall in very good condition. This is another must for the porcelain collectors library. This set is extremely tough to find and my price of $12 plus $3 media mail shipping is more than fair.