No doubt the best ever insulator history and guide. Published in 1990 and very few copies become available because collectors just don't give them up. This 2 volume set contains over 500 pages of history and photos. If you consider yourself a serious insulator collector this set is a must. The set that I'm offering is in very good used condition. I'm asking $50 for the set plus an additional $5 to cover the media mail cost anywhere in the U.S.