Applicable to screw types as indicated by code symbols.
  • Type AB thread forming.
  • 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

N/A Industrial Fasteners Institute

Specifications

Product

N/A Tapping Screws

Unit of Measure

N/A English

Nominal Size or Basic Screw Dia.

N/A 5/16 in

Nominal Size or Basic Screw Dia. (Decimal)

N/A 0.3125 in

Head Size

N/A 1/4 in
Applicable to Screw Types1 N/A 1
3
4

Max. Head Dia. (A)

N/A 0.477 in

Min. Head Dia. (A)

N/A 0.442 in

Ref. Head Side Height (H)

N/A 0.130 in

Ref. Head Crown Height (C)

N/A 0.079 in

Ref. Total Head Height (O)

N/A 0.202 in

Ref. Head Radius (R)

N/A 0.038 in

Min. Shoulder Dia. for Other Types Long Screws (E)

N/A 0.302 in

Codes and Standards

Codes and Standards

N/A Abstract of ASME B18.6.4 1998
  • 1 1 = Circle, 2 = Diamond, 3 = Triangle, 4 = Square
Use trailing wildcard (*) for broader results.