Professional Strength Teeth Whitening Kit I was really impressed by the inclusion of the UV light- it REALLY makes a big difference! I've used a number of teeth whitening kits, strips, gels, toothpastes- ad infinitum and none of them seemed to make much of a noticeable difference. Apparently the light is what makes all the difference because this made a noticeable change after the first application. I think too many people aren't really reading the instructions too closely because this is really easy to use. DON'T use too much gel! Each syringe holds enough gel for lots of applications, they say 5, but I'd say closer to 10. I have veneers, but decades of coffee, red wine, tea and smoking has really made them stained. Most whiteners don't work on veneers but I had no problem. Hooray!