This round double convex high optical purity glass lens is designed for physics and educational uses. It is approximately 2" (50mm) diameter and 5.5mm thick. Note, thickness varies as they are not designed to be consistent in that respect. Because of their educational use design, there may be minor imperfections that do not affect physical function. 150mm Focal Length

Round double convex high optical purity glass lens designed for physics and educational uses.