Maximum Bore = 1 1/4 inch To 2 1/2 inch ; Minimum Bore = 7/16 inch ; Overall Length = 2 3/4 inch To 4 inch ; Set Includes = FL51-7SB , FL51-7LB , FL51-8SB , FL51-8LB ; Shank Diameter = 1/2 inch ; Type = Indexable Boring Bar Set ;