Price is for one volume, These are Volumes of Perpetual Trouble Shooter's Manual by John Rider volumes 7,10,12,17,15,6,19,18, and the 1-5 appendix
These books are filled with schematics and have great illustrations inside. These were used in the the 1930'- the 1950's to repair radio and tube tvs.
In useable condition, they were sitting in a tv repair shop for 70 years. I will break up and sell individually for $25 a piece.