This is the RX Prescription Lenses for the Promate Fish Eyes Mask Series - Optical Lens(Bi focal and Far Sighted) Features: Prescription mask avaibale: Item code MSK37 Please note there will be an additional 2 to 3 days processing time for most RX lenses Cost is per single lens only Extra wide and long lenses provide wider peripheral view and downward vision. Ultra Low volume. Tempered glasses. Optical lenses available from -1.0 to -8.5 by increments of 0.5 (for near sighted). Optical lenses available from +1.0 to +4.0 by increments of 0.5 (for far sighted). Bifocal / Gauge Reader lenses available from +1.0 to +4.0 by increments of 0.5. RX Prescription Lenses for the Promate Fish Eyes 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.