Doubling Total Magnification power of your Microscope and reduce the focus length. 1-3/4" (42mm) Mounting Thread. Objective Magnification Power by 0.7 - 4.5X(about 10 - 180X on the display, using 0.3X 0.5X 0.75X 2.0X Barlow Lens about 2.45 - 360X on the display).
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