This device is applicable to all-level measurement testing departments, spectacles manufacturers, spectacles retail stores, hospitals or clinics of ophthalmic departments, and some optical elements factories for conducting measurement of spherical and cylindrical diopter, astigmatism axis angle of cylindrical lens, and prism basal angle.

Features:
• ±20D measurement range
• Wide observation vision field
• Classic shape, Favorable price
• Both power: DC or AC