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 Air Force 
Dept. of the Navy 
Singapore 
Republic of Korea Classification: Other articles of nickel, nesoi (excluding cloth, grill & netting of nickel wire)
NSN 5930-01-532-1724
NSN 6220-01-384-2253
NSN 5990-01-084-0807
NSN 6150-00-365-1711
NSN 5935-01-322-0285
NSN 6620-01-012-2852
NSN 6685-01-500-1810
NSN 6135-01-069-2482
NSN 5998-01-296-7325
NSN 6130-01-656-3234
NSN 6620-00-551-9948
NSN 5960-00-212-6367