A screw, machine or screw, cap, socket head whose unthreaded portion is of specified grip length, plated or unplated, and is machined to a tolerance of one thousandth (0.001 in.) (0.025 mm) or less of a specific diameter for items (1.000 in.) (25 mm) or less in diameter. Items over (1.000 in.) (25 mm) in diameter shall have a tolerance of fifteen ten thousandths (0.0015 in.) (0.038 mm) or less. The nominal major diameter of the threads shall be at least one thousandth (0.001 in.) (0.025 mm) below the minimum shank diameter, but not below the minimum major diameter for applicable class of fit, as shown in the screw thread standards, fed std h28 and/or other nationally recognized standards. The head is designed to be held or driven with an inserted driver. It is not designed for rotation by the thumb and fingers. A locking feature may be incorporated in the design of the head or threads.
Dept. of the Navy 
Spain Classification: Other articles of nickel, nesoi (excluding cloth, grill & netting of nickel wire)
NSN 6130-01-167-9371
NSN 2925-00-471-1128
NSN 6620-01-308-2692
NSN 2925-00-480-9068
NSN 5855-00-688-9954
NSN 6145-01-484-6698
NSN 6620-01-470-1058
NSN 2925-00-918-0859
NSN 5915-01-192-9000
NSN 5920-01-081-1267
NSN 6610-01-242-3760
NSN 5945-01-006-9422