The Essilor PAL-ID eliminates the possibility of errors in fitting progressive addition lenses by providing a clear view of etchings. Easily identify manufacturer, model, material, and reference points. Simply hold the lens between the light source and the polarized filter with heavy magnification. Once focused, engravings appear three dimensionally embossed, and are easily viewed and marked. Confirm all power engravings, regardless of the age or condition of the lens.