These DVD's were edited from gunsmith training course materials and were originally available only as companion videos for the Kuhnhausen Colt .45 Auto, S&W Revolver, and Volume I Colt D.A. Revolver Shop Manuals.They add extra chapters to their corresponding manuals, all three programs stand by themselves and provide additional practical gunsmithing information.Gunsmithing the Colt .45 Automatic (and M1911-M1911A1 copies) Gunsmithing the S&W J, K, L, & N Frame Revolvers (non powdered metal part revolvers manufactured through mid 1999) Gunsmithing the Colt D, E, & I Frame Series Revolvers (Python, Official police, Det. Special, Agent, Diamondback, etc.)