The 1st time I tried 'Snow' I used the ultrablue light mouth piece for 30 minutes. My teeth are whiter. I now use Snow every night using my ultralight mouth piece & I leave it in for the full 30 minutes. I will keep using it every night, so my teeth will stay white. I'm a huge fan of Snow. Thank you, Toni minutes. . before every night. It's a month later & my teeth are very white. I use the mouth piece, full 30 the Snow ultrablue light mouth piece every night, for the full 30 minutes. been over a month now. night with the ultrablue l've used Snow every night for a month now. I leave it in for a full 30 minutes every night , levery I've been using Snow for over a month, using the ulrablue light 30 minutes every night & I am so happy, my teeth are white. My boyfriend was like Wow! I will keep using this incredible Snow Teeth Whitening. Thank You this Amazing Product. Blessings, Toni