Map reading glasses. Very popular with orienteers requiring eye protection & magnification
Full glasses with bi-focal magnifier in lower part of lens help map reading while running
Supplied with a clear lens. Also good for cycling
Polycarbonate lens for good protection when running in the forest etc.
Diopter strength: 1.0, 1.5, 2.5, 3.0, 3.5 give good magnification