The trial frame can accommodate up to four pairs of lenses. Easier to use and comfortable to wear. Features easily changeable cylinders. Fully adjustable temple length and nose rest. Horizontal and vertical bridge adjustments. This optical trial lens frame allows for accurate refraction, even with complex prescriptions, and provides comprehensive adjustments for a proper and comfortable fit. Separate PD adjustment for each eye. Individual temple length adjustments. Adjustment for rotating cylinders. Equipped with clear scales and large numerals. Available in metal or plastic construction. Lens holder diameter: 38mm. Pupillary distance (PD) adjustment range: 48 - 80mm. Package includes: 1 x Trial Frame. Note: Lighting and display differences may cause slight variations in color between the image and the actual item. Measurement may vary by +/- 1-3cm.