• Where specifying nominal size in decimals, zeros preceding decimal and in the fourth decimal place shall be omitted.
• 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, Appendix; and Types D, F, G, and T thread cutting.
• No tolerance for gaging diameter is given. If the gaging diameter of the gage used differs from tabulated value, the protrusion will be affected accordingly and the proper protrusion values must be recalculated using the formulas.
• Short screws are those threaded full length.

This type of recess has a large center opening, wide straight wings, and blunt bottom, with all edges relieved or rounded.