This Springfield Armory manufactured late variation cam latch screw (aka breech block cap screw) is for the later model 1873 trapdoor rifle and carbine and is in very good condition exhibiting a grayish brown patina with light slot wear.  (file photo)

 Note: Trapdoor rifles and carbines with serial numbers above circa 87,000 would have used this late variation screw having the beveled edge along the radius of the head.

Note: U.S. Springfield Armory model 1873 trapdoor firearms with the following serial numbers have been observed with this part: 89587 & 130964