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 
Republic of Korea Classification: Bolts and bolts and their nuts or washers exported in the same shipment
NSN 5998-01-053-0023
NSN 6320-01-250-0290
NSN 5950-01-133-5569
NSN 5985-01-320-0957
NSN 5895-01-258-4382
NSN 5998-01-407-7427
NSN 6135-01-582-5987
NSN 7035-00-631-3782
NSN 5920-01-050-6557
NSN 5998-01-109-8169
NSN 5895-01-271-7215
NSN 6145-01-087-3320