Professional quality optics iGaging is the professionals choice. Designed to provide an undistorted flat field of view larger and brighter than similar magnifiers with its type of power. Make precise measurements with its scale from 0-0.18" by 0.002". Always in focus! No moving parts. Compound lens system of four parts gives accurate readings Clear graduation scale 0-0.18" by 0.002"Super clear vision. Anodized aluminum body, glass lenses.