Commercial Knob Lockset - Type Tulip - Preston Style - Grade 2 - For Door Thickness 1 3/8 To 1 3/4 In - Backset 2 3/8 Or 2 3/4 In - Crossbore Size 2 1/8 In - Keying Different - 2 1/4 X 1 3/4 In T Strike - Required Door Thickness 1 3/4 In