800 Contact Lenses

contact lenses
A thin plastic lens placed directly on the surface of the eye to correct visual defects
(contact lens) contact: a thin curved glass or plastic lens designed to fit over the cornea in order to correct vision or to deliver medication
(contact lens) A thin lens, made of flexible or rigid plastic, that is placed directly on to the eye to correct vision, used as an alternative to spectacles, or, if coloured, to change one's eye color cosmetically
(Contact lens) A small plastic disc containing an optical correction that is worn directly on the cornea as a substitute for eyeglasses.

800
Year 800 (DCCC) was a leap year starting on Wednesday (link will display the full calendar) of the Julian calendar.
A toll-free, Freecall, Freephone, or 800 number is a special telephone number, in that the called party is charged the cost of the calls by the telephone carrier, instead of the calling party.
The 800 Apartments is a skyscraper in Downtown, Louisville, Kentucky. The building is named after its address of 800 South Fourth Street.