Donegan OptiVISOR LX Binocular Magnifier-Lensplate #4 Magnifies 2X At 10" Focal Length
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Donegan DA-5 OptiVisor Headband Magnifier, 2.5x Magnification, 8 Focal Length
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Optivisor Lens Head Magnifier Glasses Magnifying Visor Glass Headband 4 Lenses
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Donegan Optical OptiVISOR Binocular Magnifier-Lensplate #5 Magnifies 2.5x At 8"
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