Here is a Bausch & Lomb Rapid Rectilinear brass lens from about 1880.  The focal length looks to be about 4 inches.  It is 1-3/4 long.  The front and rear bezels are 40mm and the mounting threads are 44mm.  I have no mounting ring for this.  The aperture blades are missing.

There will be no bids accepted from or shipping to China or the Russian Federation.

Thanks for your purchase.