Item # HHS13750XXX, Heavy Hex Screw, 1-3/8" Nominal Dia. On Sales Systems Ltd.

Top of Head. Top of head shall be full form and chamfered with the diameter of chamfer circle being equal to the maximum width across flats, within a tolerance of minus 15%.
Wrenching Height, J. Wrenching height is a distance measured from the bearing surface up the side of the head at the corners. The width across corners shall be within the specified limits for minimum wrenching height.
Bearing Surface. Bearing surface shall be flat and washer faced. Diameter of washer face shall be equal to the maximum width across flats within a tolerance of minus 10 percent.
Thickness of the washer face shall be not less than 0.015 in. nor greater than 0.025 in. for screw sizes 3/4 in. and smaller, and not less than 0.015 in. nor greater than 0.035 in. for sizes larger than 3/4 in. Measurement of washer face diameter shall be taken at a height of 0.004 in. above the bearing surface.

Unit of Measure

Manufacturer | Specifications | Codes and Standards | Thread Length for Screw Lengths

N/A Industrial Fasteners Institute

Product	N/A Square and Hex Bolts and Screws
Unit of Measure	N/A English
Nominal Size or Basic Product Diameter	N/A 1-3/8 in
Nominal Size or Basic Product Diameter (Decimal)	N/A 1.3750 in
Max. Body Diameter (E)	N/A 1.3750 in
Min. Body Diameter (E)	N/A 1.345 in
Basic Width Across Flats (F)	N/A 2-3/16 in
Max. Width Across Flats (F)	N/A 2.188 in
Min. Width Across Flats (F)	N/A 2.119 in
Max. Width Across Corners (G)	N/A 2.526 in
Min. Width Across Corners (G)	N/A 2.416 in
Basic Head Height (H)	N/A 27/32 in
Max. Head Height (H)	N/A 0.878 in
Min. Head Height (H)	N/A 0.810 in
Min. Wrenching Height (J)	N/A 0.569 in
Max. Transition Thread Length (Y)	N/A 0.833 in
Max. Circular Runout of Bearing Surface FIM	N/A 0.038 in

N/A ASME B18.2.1 1996

Nom. L_T for Screw Length (6 in. and Shorter)	N/A 3.000 in
Nom. L_T for Screw Length (Over 6 in.)	N/A 3.250 in

Manufacturer