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		                             National Stock Number: 5305-00-040-9780
  Federal Supply Class: 5305
  National Item Identification Number: 000409780
  Description: SCREW,CLOSE TOLERANCE
  Detail: 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. 
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  Manufacturer Information:
 | 39-25088-1 | 82918 | THE BOEING COMPANY |   
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  Techincal Specification:
 | THREAD SERIES DESIGNATOR | UNJF |  | NOMINAL THREAD DIAMETER | 0.250 INCHES |  | THREAD QUANTITY PER INCH | 28 |  | THREAD CLASS | 3A |  | THREAD DIRECTION | RIGHT-HAND |  | THREAD LENGTH | 0.290 INCHES MINIMUM AND |   | 0.340 INCHES MAXIMUM |  | FASTENER LENGTH | 0.930 INCHES MINIMUM AND |   | 0.960 INCHES MAXIMUM |  | MATERIAL | STEEL COMP 4340 OVERALL |  | SURFACE TREATMENT | CADMIUM AND |   | CHROMATE OVERALL |  | SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416,TYPE 2 CLASS 3 FED SPEC ALL TREATMENT RESPONSES OVERALL |  | HARDNESS RATING | 33.0 ROCKWELL C NOMINAL OVERALL |  | MINIMUM TENSILE STRENGTH | 160000 POUNDS PER SQUARE INCH |  | HEAD STYLE | FLAT CHAMFER |  | HEAD DIAMETER | 0.498 INCHES MINIMUM AND |   | 0.500 INCHES MAXIMUM |  | HEAD HEIGHT | 0.740 INCHES MINIMUM AND |   | 0.760 INCHES MAXIMUM |  | INTERNAL DRIVE STYLE | SLOT |  | GRIP LENGTH | 0.620 INCHES MINIMUM AND |   | 0.640 INCHES MAXIMUM |  | GRIP DIAMETER | 0.2485 INCHES MINIMUM AND |   | 0.2495 INCHES MAXIMUM |  | SURFACE FINISH | 63.0 MICROINCHES GRIP |  | THE MANUFACTURERS DATA |  |  | MANUFACTURERS CODE | 82918 |  | DESIGN CONTROL REFERENCE | 39-25088-1 |   
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