I happen to wear this lens. This lens enable us to wear reading (short vision) and distant vision lenses in only one pair of glasses, so that it's useful in giving practicality rather than if we have to bring two glasses all the time and wear them alternately.
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They are special eye lenses that correct your eye-sight. They correct: distance vision, arm-length vision, and near vision.
They are very useful is you happen to have these eye disturbances. It might be worth the money if you really need to correct your eye-sight. Although I would suggest going to an optician before taking this decision.