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 1/4 in

Nominal Size or Basic Screw Dia. (Decimal)

N/A 0.2500 in
Applicable to Screw Types1 N/A 1
3
4

Max. Head Dia. (A)

N/A 0.414 in

Min. Head Dia. (A)

N/A 0.389 in

Max. Head Side Height (H)

N/A 0.170 in

Min. Head Side Height (H)

N/A 0.155 in

Max. Total Head Height (O)

N/A 0.237 in

Min. Total Head Height (O)

N/A 0.207 in

Max. Slot Width (J)

N/A 0.075 in

Min. Slot Width (J)

N/A 0.064 in

Max. Slot Depth (T)

N/A 0.109 in

Min. Slot Depth (T)

N/A 0.087 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.