I would like to order a pair of single vision distance glasses with the automatic color change to gray in sunlight, do you know what does that type lenses call, and where can i get them?
Thanks for your help!

I think you want to buy to photochromic lenses which are clear indoors and darken automatically outdoors. Have you bought prescription glasses from the online stores? They are your good choices as they supply phtochromic lenses at much cheaper price than the ones at retail stores. You may get on the online optical store PrescriptionGlassesOnline.net and have a look, my colleague just bought his new eyeglasses from it.