Never buy colored contact lenses from a retailer that does not ask for a prescription. There is no such thing as a "one size fits all" contact lens. Lenses that are not properly fitted may scratch the eye or cause blood vessels to grow into the cornea. Learn more how some retailers are selling illegal contact lenses!
Contact lenses are prescription medical devices. Even if you just want to purchase cosmetic contact lenses that change your eye color, you will still need an eye exam and a prescription from an eye doctor. The same applies to costume or theatrical contact lenses. Watch the video on how to wear them!