Use an Allen wrench (hex key) to secure with required torque as needed.Size: #4-40 X 1/4 inchHex (Allen) DriveInstalls using an Allen wrenchCan be used in tight spaces where there may not be room for a socket tool or wrenchOften used in machinery, tools & diesThread Type: Coarse, Thread Class: UNC-3A, Point Style: BluntSpecification(s) Met: ASME B18.3 & ASTM A574 Rounded head has splined outer circumference with internal hex drive..
83 mm, Drill Bit Point Angle 130 Degrees , High Speed Steel, Decimal Equivalent 0.Jobber Drill Bit, Drill Bit Size 2.1114, Metric, Drill Bit Point Type S Thinning Point, Non-Coolant Through.