This is a rather hard to find NOS, new old stock, carburetor for a Briggs and Stratton air cooled gas engine.  I believe it was used on several models of their engines.  It mounts with two holes 1 13/16 inches apart on center.  It has a 15/16" hole in the mounting flange and a 1 5/16 hole in the intake.  Everything is in great shape and moves as it should.  This carburetor should be ready to go to work on an engine!  These NOS carburetors are quite tough to find in the wild or even at swap meets so if you need one to complete a restoration here it is.  It would also make a great spare in your inventory. The pictures tell the story.  I can be reached at 262 573 193 1 if you'd like to talk about it.  Good Luck.