I wear contact lenses for about 6 years and have in vain been tried several products. I not alternately too irritating my eyes must wear my glasses and contact lenses, I thought, these lenses are the solution. I also have every six months to check my eyesight because this is getting worse from year to year. So far I have (at least for contact lenses) used always -3.75 diopters. With these lenses but I see very blurry in the distance. Somewhat confused, I have therefore checked my vision again, but on this has thankfully !! nothing changed. It seems that the lenses are not as strong as my previous (despite the same diopter number). To be fair, I have to say that they can be worn very pleasant and use. Nevertheless, the copies purchased by me are unfortunately can serve only as a substitute lens.