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		                        | National Stock Number:
 5305-01-495-9323
 
 Federal Supply Class:
 5305
 
 National Item Identification Number:
 014959323
 
 Description:
 SCREW,CAP,SOCKET HEAD
 
 Detail:
 An externally threaded fastener whose threaded portion is of one nominal diameter. The head has an internal socket or multiple spline for use with an inserted driver. A locking feature may be incorporated in the design of the head or threads. Excludes items with bevel (conical) heads. See BOLT, INTERNAL WRENCHING. Excludes SCREW, SHOULDER; and SCREW, MACHINE.
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 Manufacturer Information:
 
 | 0.250-20UNRC-3A0.500LG NICUAL | 81349 | MILITARY SPECIFICATIONS PROMULGATED BY MILITARY DEPARTMENTS/AGENCIES UNDER AUTHORITY OF DEFENSE STANDARDIZATION MANUAL 4120 3-M |  | 596-7409350-3 | 53711 | NAVAL SEA SYSTEMS COMMAND |  | FF-S-86 | 81348 | FEDERAL SPECIFICATIONS PROMULGATED BY GENERAL SERVICES ADMINISTRATION WASHINGTON DC |  | B541-1301-3 | 96169 | ELECTRIC BOAT CORPORATION | 
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 Techincal Specification:
 
 | COUNTERSINK ANGLE | 82.0 DEGREES NOMINAL |  | FASTENER LENGTH | 0.500 INCHES NOMINAL |  | HEAD DIAMETER | 0.480 INCHES MINIMUM AND 0.531 INCHES MAXIMUM |  | HEAD STYLE | FLAT COUNTERSUNK |  | INTERNAL DRIVE STYLE | HEXAGON |  | LOCKING FEATURE | PATCH THREADS OR PELLET THREADS OR STRIP THREADS |  | MATERIAL DOCUMENT AND CLASSIFICATION | QQ-N-286,CL A FED SPEC SINGLE MATERIAL RESPONSE OVERALL |  | MATERIAL | NICKEL ALLOY K-500 OVERALL |  | PROPRIETARY CHARACTERISTICS | PACS |  | NOMINAL THREAD DIAMETER | 0.250 INCHES |  | NONDEFINITIVE SPEC/STD DATA | 4 TYPE |  | SPECIAL FEATURES | TECH DATA NOT AUTHORIZED FOR RELEASE OUTSIDE OF U.S.; PART OF LDT TRANSFER UPPER RAILS ASSEMBLY OF SSN 23 SEAWOLF CLASS SUBMARINE |  | WIDTH ACROSS FLATS | 0.156 INCHES NOMINAL |  | THREAD CLASS | 3A |  | THREAD DIRECTION | RIGHT-HAND |  | THREAD LENGTH | 0.339 INCHES NOMINAL |  | THREAD QUANTITY PER INCH | 20 |  | THREAD SERIES DESIGNATOR | UNRC | 
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