Applicable to screw types as indicated by code symbols.
  • Types B and BP thread forming and Types BF and BT thread cutting.
  • Type C thread forming and Types D, F, G, and T thread cutting.
Unit of Measure

Manufacturer

Manufacturer

Industrial Fasteners Institute

Specifications

Product

Tapping Screws

Unit of Measure

English

Nominal Size or Basic Screw Dia.

3/8 in

Nominal Size or Basic Screw Dia. (Decimal)

0.3750 in
Applicable to Screw Types1 3
4

Length for Other Types (LT)

5/8 in

Max. Head Dia. (A)

0.717 in

Min. Head Dia. (A)

0.670 in

Ref. Head Side Height (H)

0.161 in

Ref. Head Crown Height (C)

0.117 in

Max. Total Head Height (O)

0.278 in

Min. Total Head Height (O)

0.239 in

Max. Slot Width (J)

0.094 in

Min. Slot Width (J)

0.081 in

Max. Slot Depth (T)

0.179 in

Min. Slot Depth (T)

0.149 in

Max. Protrusion Above Gaging Dia. (F)

0.182 in

Min. Protrusion Above Gaging Dia. (F)

0.139 in

Gaging Dia. (G)

0.653 in

Codes and Standards

Codes and Standards

Abstract of ASME B18.6.4 1998
  • 1 1 = Circle, 3 = Triangle, 4 = Square
Use trailing wildcard (*) for broader results.