Invented by Professor Joshua Silver, the Adspecs were the first available self-adjustable glasses that allow the wearer to tune their glasses to their eyes. To change the power of the lens. Turn the dials slowly on the side-arms until each eye can see clearly. Press the buttons on the frame to seal the lenses in place, detach the adjuster tubes and prevent further adjustment. Unclip the adjusters from the side-arms and dispose of them safely. The glasses are now set and sealed and function like normal spectacles.
For more information about the glasses, visit the Center for Vision in the Developing World.