This is the optical quality, single vision MV Optical Model 27 with aspheric optical reading lenses. The high end, optical quality acetate frame shape is a modern, classically rectangular shape frame sized for an average head size (unisex). These single vision aspheric lens reading glasses are available in any power from +1.0 all the way up to +6.0. A Single Vision Poly Aspheric lens is the latest in reading lens technology: Impact Resistant, Thin Light Weight, scratch resistant and includes 100% UV protection. A Poly Aspheric lens really makes a difference, especially in higher powers, since the lens will be thinner and thus, more lightweight. There is noticeably less magnification of your eye and the wearer gets better peripheral vision. Style 27 has a smooth acetate finish with spring hinged temples. Available in either a smooth Tortoise, Grey Marble or black finish. Includes a clam shell design hard protective case. Please note that the higher powers of +4.5, +5.0, +5.5 or +6.0 cost an additional $10. Style 27 is sized for an average unisex head size. Here's the optical sizing scoop on Style 27: Lens: 52mm, Bridge: 16mm, Temple: 140mm