This part is a kind of semiconductor called MS21042.

Function of this product has Nuts.

Manufacturers : Coast Fabrication

Image and pinout :

Some of the text within the PDF file :

MS21042 / NAS1291 Series Specifications Nuts, Self-locking, 450°, Reduced Hexagon, Reduced Height, Ring Base, Non-Corrosion Resistant Steel 35 Size Dash No. 02 04 06 08 3 4 5 6 7 8 9 10 Thread a 2-56 UNC-3B 4-40 UNC-3B 6-32 UNC-3B 8-32 UNC-3B 10-32 UNF-3B 1/4-28 UNF-3B 5/16-24 UNF-3B 3/8-24 UNF-3B 7/16-20 UNF-3B 1/2-20 UNF-3B 9/16-18 UNF-3B 5/8-18 UNF-3B A Max .167 .206 .244 .290 .330 .420 .520 .620 .708 .814 .912 1.014 B Min .137 .176 .214 .260 .290 .386 .482 .575 .680 .786 .874 .976 C Min .138 .171 .207 .244 .277 .347 .419 .491 .562 .633 .775 .846 D Max .106 .142 .168 .194 .220 .280 .342 .405 .467 .530 .592 .655 Min .086 .112 .138 .164 .190 .250 .312 .375 .437 .500 .562 .625 Ed Min .045 .050 .055 .060 .065 .090 .120 .125 .160 .225 .320 .365 Fe Min .019 .028 .039 .041 .043 .057 [ ... ]

MS21042 PDF Datasheet Download