I guess this is the best product in the market when it comes to contact lenses, I have tried lenses of other companies too but I ended up with red swollen eyes each time I wore them. Ciba Vision O2 Optix lenses are so light that you don’t even feel you’re wearing contact lenses. They are durable and comfortable. The Silicone hydrogel material they have used to make these lenses consists of approx. 67% lotrafilcon B and 33% water. That’s what makes this so easy on your eyes and that’s why I have been using it for. Thank you Ciba Vision. Keep up the good work.