This is an original eyepiece that came with the Cave Telescope. Orthoscopic 10.5 mm eyepiece with a 50 degree field of view. All glass air surfaces are hard coated to improve light transparency and are true Orthoscopic in design, having a triple achromatic field lens and a single eye lens. This occular is a fine example of a quality eyepiece of its day and made in Japan. Quite heavy by todays standards and in very good to excellent condition. The barrel of this example is in especially fine shape.