A 155-page illustrated manual on lock picking and impressioning with hundreds of photos including microscopic views. You'll see exactly what impression marks look like on different key blanks and learn to recognize when you've achieved correct pick feedback.
Covers pin tumbler, wafer, lever, push key, warded, and tubular mechanisms. The impressioning section shows file techniques, mark interpretation, and progressive filing methods. More photos and less theory than most picking books - focuses on showing you what to look for rather than explaining physics.