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BACB30LU4-3

Close Tolerance Screw

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Description

Fastener Length: 5/8", Thread: 1/4-28, Thread Length: 7/16

Specifications

Countersink Angle 100.0 degrees
Fastener Length Between 0.598 inches and 0.628 inches
Grip Diameter Between 0.2485 inches and 0.2495 inches
Grip Length Between 0.178 inches and 0.198 inches
Head Diameter Between 0.455 inches and 0.510 inches
Head Style Flat countersunk
Internal Drive Style Cross recess type 1
Length 5/8
Material Steel
Surface Finish 32.0 microinches grip, 32.0 microinches threads
Surface Treatment Cadmium and chromate
Surface Treatment Specification Cl 3 federal specification single treatment response type 2 qq-p-416
Thread Class 3a
Thread Diameter 0.250
Thread Direction Right-hand
Thread Length Between 0.400 inches and 0.450 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

Similar parts

Parts with matching key dimensions — often from a different standards family. Candidates for comparison only; verify the full specification before substituting.

  • NAS7104-3 NAS 1/4-28 · 5/8 in · Flat countersunk · Steel

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