The Fantasia has been a best selling mask for years because of it's versatility. Fits a wide range of faces and is corrective lens compatible. Please message us at firstname.lastname@example.org if you choose to purchase your mask with prescription or bifocal lens with your preferred diopter strength. Full lens prescription available in Diopters -8.0 to +3.0. Bifocal lens available in +1.75, +2.25 and +2.75.