MS16997 alloy-steel UNC socket-head cap screws.

// REFERENCE SIZES

MS16997 part-number and dimension table

Reference sizes for identification and quotation; availability is confirmed by inquiry. These rows do not indicate Webson stock.

Head diameter and socket AF are minimum–maximum limits; head height is a maximum from the reviewed MS16997D reference. Length is nominal and measured beneath the head. Socket AF means socket width across flats; these limits are not a nominal hex-key size.

// LENGTH CONVENTION

Measure the correct length

Length is measured from beneath the head to the tip. MS16997-32 is an 8-32 by 1/2-inch reference; MS16997-58 is a 1/4-20 by 1/2-inch reference. Longer screws can have an unthreaded body. Overall under-head length is not the same as thread length or grip length.

// ORDERING DETAILS

Keep finish and locking codes with the part

The reviewed MS16997D notes specify alloy steel and cadmium plating under the procurement specification. An L after the dash number identifies the self-locking version: MS16997-1 is plain, while MS16997-1L has a self-locking element. The rows in this table identify plain screws; preserve any required locking suffix in the inquiry.

// RELATED REFERENCES

Compare related screw families

// DRAWING REQUIREMENTS

Use the issue required by your drawing

Dimensions summarize MS16997D, sheets 1 and 3, 31 December 1976. This is a selected purchasing reference. Send the complete part designation and governing specification issue for quotation; the required issue controls full dimensions, tolerances, material, finish and documentation.