This is the RX Prescription Lenses for the Promate Scanner Mask Series - Optical Lens Features: Prescription mask available item code: MSK70 and MSK72 Please note there will be an additional 2 to 3 days processing time for most RX lenses Cost is per single lens only Ultra low volume Broad peripheral view Tempered glasses Optical lenses available from -1.0 to -10.0 by increments of 0.5 (for nearsighted/myopic) Optical lenses available from +1.0 to +4.5 by increments of 0.5 (for farsighted/hyperopic) Bifocal / Gauge Reader lenses available from +1.0 to +4.0 by increments of 0.5. (top plain without prescription, bottom with magnifier reader) RX Prescription Lenses for the Promate Scanner Mask Series - Optical Lens(Bi focal-Gauge Reader and Far Sighted). Returns are not accepted for used lens. Only unused lens are eligible for return with store credit.