Welch Allyn® 3.5V Retinoscope Provides superior illumination and is designed for accurate refraction. Unique one-hand operation and the comfort of a rubber brow rest. External focusing sleeve is easy to grip and manipulate. Crossed-linear, polarizing filter eliminates glare from trial lenses for easier exams. Magnetic age-appropriate targets for dynamic retinoscopy. Allows easy one-hand operation for streak focus and 360° streak rotation. Interchangeable streak retinoscope can be converted to a spot retinoscope by simply changing the lamp.