Caffeine Shampoo Conditioner with Biotin, Argan Oil, Rosemary, Niacinamide for Strong and Thinning Hair...Well, normally I do not review a product quickly, but this is exceptional! I have been using it for about 2 weeks, and I have had a great experience! The first time, not very impressive, the reason I realised later is that I washed them immediately (1 minute ) due to my habit. I did feel the difference after the use of the conditioner. I then read the instruction, alas, 4-5 minutes! Did I miss something?Yes, the second time, I left the shampoo on my scalp and hair, massaged slightly, and felt better after minutes! Then I used the conditioner, even better than the shampoo, absolutely. More precisely, the conditioner introduced a cooling sensation on the scalp! From the second use, I found the best time for shampoo is about 4-5 minutes and for the conditioner, 5-10 minutes. I used to have quick showers, but now enjoy a long and comfortable experience, simply amazing.I feel refreshed after the shampoo and conditioner, each time. I do not know the reason but it does happen to me. My hair, becomes softer and more shiny, no I do not say silky, but much better! My scalp? I do love the tingling sensation and have never this experience before!So I'm a happy man with healthier hair and scalp now. I sued about 4 times a week as I'm not sure if it's better for more frequent use.I do not say my hair much thicker as it takes time. I will defy use it and buy more as I feel it worth…