Olympus S Plan Fluorite 1X Microscope Objective.  This is a dealer demonstrator and it will fit the Olympus BH2, BHTU, BHS, Vanox, and IMT-2 series of microscopes.  It also works wonderfully well on other 160mm tube length microscopes from Zeiss, Leitz and Nikon.  All glass surfaces are free from fungus, dust, scratches, oil fouling of interior elements or element separation.  It has an N.A. of 0.04 and a W.D. of 2.20mm.  This objective gives fantastic images. The Olympus product number is 1LB511 with a list price of $1,166.00.