This part is a kind of semiconductor called NAS77.

Function of this product has Unlined Flanged Bushings.

Manufacturers : RBC

Image and pinout :

Some of the text within the PDF file :

FLANGED BUSHINGS NAS77 UNLINED FLANGED BUSHINGS • Material options: Aluminum bronze, beryllium copper, alloy steel, CRES • Finish options: Cadmium plating, aluminum coating • A final size (FS) option is available. Parts are manufactured to customer’s required dimensions D + .000 .062 - .005 L ± .005 + .0000 UNLESS OTHERWISE + .0010 SPECIFIED IN TABLE H ± .010 + .0015 B - .0000 O.D. .005 .015 x 45° I.D. .025 .035 x 45° CHAMFER BOTH ENDS (SEE NOTE 6) .062 MAX WHERE L IS .250 INCHES AND LONGER .015 MAX WHERE L IS LESS THAN .250 INCHES .005 R .002 .005 MAX UNDERCUT OPTIONAL .005 R .002 .010 .005 SPECIFICATIONS AND ORDERING INFORMATION DIMENSIONS TOLERANCES B Part Number +.0015, -.0000 +.038, -.000 in. NAS77A3-xxx NAS77A4-xxx NAS77A5-xxx NAS7 [ ... ]

NAS77 PDF Datasheet Download