This Stevens manufactured lever spring is for the Favorite single shot falling block rimfire rifle which is supported on the inside by the screw that attaches to the threaded hole in the forward belly of the receiver between the takedown screw and the lever. This lever spring is in very good condition exhibiting a grayish brown patina with light wear. (file photo)

Note: this part is commonly found on the Stevens Favorite single shot rifle with a 3rd thru 6th variation receiver.