This Springfield Armory manufactured early variation breech screw (aka tang) is for the model 1873 trapdoor rifle and carbine in 45-70 Govt. caliber and is in very good condition exhibiting a dark oil quenched blue finish mixed with a brown patina and some specks of rust and/or pin prick pitting.  (file photo)

 Note: Model 1873 trapddor rifles and carbine with serial numbers below circa 81,000 would have had this oil hardened finish.