The EXTREME DUTY FIXED SIGHT conversion will convert your adjustable sight K,L,or N frame Smith & Wesson revolver to a fixed sight tactical revolver. The rear sight blade on the adjustable rear sight on a Smith & Wesson revolver is very prone to snagging on your clothing and being broken off when exiting a vehicle or during a takedown. The EXTREME DUTY FIXED REAR SIGHT is contoured to completely eliminate the problem of snagging on your clothing during a speed draw, or breaking off when struck during a vehicle exit or takedown. Comes with a .330" x 65 11 dovetail front sight.