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NAS1578A4T6

Close Tolerance Screw

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Description

length: 0.778", thread: 1/4-28, flat pan head, alloy steel offset cruciform, NAS1578 series screw

Specifications

Fastener Length Between 0.763 inches and 0.793 inches
Grip Diameter Between 0.2485 inches and 0.2495 inches
Grip Length Between 0.367 inches and 0.385 inches
Hardness Rating 36.0 rockwell c and 40.0 rockwell c
Head Diameter Between 0.477 inches and 0.492 inches
Head Height Between 0.140 inches and 0.150 inches
Head Style Pan no. 2
Internal Drive Style Offset cruciform (torque set)
Material Steel
Min. Tensile Strength (psi) 160000 pounds per square inch
Specification Data 80205-nas1578 professional/industrial association standard
Surface Finish 32.0 microinches bearing surface of head, 32.0 microinches threads
Surface Treatment Cadmium and chromate
Surface Treatment Specification Qq-p-416 ty2 cl2 federal specification single treatment response
Thread Class 3a
Thread Diameter 0.250
Thread Direction Right-hand
Thread Length Between 0.378 inches and 0.428 inches
Thread Qty 28
Thread Qty Per Inch (tpi) 28
Thread Series UNJF
Thread Series Designator Unjf (fine thread with external controlled root radius)
Thread Size 1/4

Other sizes

Parts that share this base number, ordered by size. Always verify the full specification before substituting.

Cross-reference

No interchangeable or dimensionally similar parts are on record for NAS1578A4T6. Try the cross-reference lookup to search by a different part number.

Catalog data updated 2026-07-05. Report a data error