Didn’t work and turns yellowish-brown after a few days [SEP] I was really disappointed in this, been using it off and on for months and it hasn’t strengthened my nails at all. It also starts to oxidize in two days, getting yellow then brown so it makes my nails look like they’re  dirty! Sure enough when I removed it with acetone the cotton ball turned yellowish-brown and my own nail was actually clean underneath. Very odd effect. I wouldn’t mind the discoloration as much if it actually worked but my nails still tore, broke, remained thin and this polish chips off easily. It goes on smooth and seems thick at first, but it’s all downhill from there. Maybe the other formulas from this line work better? Wish I could get a refund!