This 134-page course teaches safe combination lock manipulation through progressive lessons. You start with wheel pack mechanics and basic contact point theory, then advance through different fence types and manipulation techniques. Each chapter ends with review questions.
The book includes actual manipulation walkthroughs showing spring fence, friction fence, direct entry, and false gate approaches. Photos illustrate what you're feeling for at each step. Designed as home study material for people who want to understand the theory and practice of manipulation.