Nikon Stereo Microscope Objective protector for the Nikon SMZ-U and SMZ 645 microscopes. It is new still in original packaging and is old stock no longer available from Nikon. The Nikon number is 83083 and to my knowledge will fit no other Nikon microscopes. PLEASE DO NOT ORDER IF YOU ARE HOPING IT WILL FIT ANOTHER SERIES AND THEN RETURN WHEN IT DOES NOT. Thanks for looking