... can focus, clear and precise.High transparency optical glass lens. YC folding Magnifier Technique parameter:Magnification: 40--100timesType: 50*23*138mmColor ... . With light, calibration, can focus, clear and precise2. Lens: High transparency optical glass (no damage to eyes).3. ... . With focus function, can see more clearly than general magnifier. Use:Printing network, note and paper; jewelry appraisal, ...