Sale Pending: Bausch and Lomb Aero-Tessar lens; 4” F/6 in nice aluminum cell; can be easily mounted in a tube to make a nice RFT. I believe that this lens is not coated. The slight loss in transmission is made up for by the excellent image quality at the edge of the eyepiece field. Lens was designed for aeriel photography from the belly of an airplane. $30 plus shipping.