ADJUSTABLE READING GLASSES: You can adjust the intensity by turning the knob on the frame. The left and right adjustment in the middle is 0 degrees, Adjust left and right to the middle to increase intensity until you reach the correct focal length. Please adjust for each eye individually until you find the right magnification intensity for each eye. Focus:1.00 to 4.00 DIMENSION: Lens Width: 48mm/1.89 inch Lens Height: 30mm/1.18 inch Frame Lenght: 142mm/5.59inch Bridge Width: 20mm/0.79 inch Arm Lenght: 145mm/5.71 inch