Acquired from NASA, only USA made hardware.  55 total military standard threaded inserts MS51831CA206L

Description:

1/2"-20 Solid Wall Insert w/ Internal Thread Lock, Iron Alloy, Passivated, Lightweight, Key Locked, 5/8" L

MFG #:MS51830CA206L

Thread Class:

3b

Length:

5/8" inches nominal

Insert Size:

1/2" unc 2a

Features Provided:

Individually keyed

Thready Qty Per Inch (tpi):

20

Thread Size:

0.375 inches

Material:

Iron alloy 660 overall

Material Specification:

Ams 5737 assn std single material response overall

Surface Treatment:

Passivate overall

Surface Treatment Specification:

Qq-p-35 fed spec single treatment response overall

Style Designator:

Grooved keylock

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