Highest Quality 540 Needles: We at mars by GHC use only the highest quality needles to produce our highly effective, gentle derma tool which is the perfect solution for maximizing results., How It Works: Derma roller prompts the scalp to produce more collagen and thus supporting the growth stage inside the hair follicle. Derma roller increases the blood flow in the scalp area., Collagen Production: Derma roller will also stimulate natural collagen production, keratin production, and activates stem-cell growth factors., How To Use: Dermarolling for hair growth is very simple. Use a derma roller on dry hair, place the derma roller where you have hair thinning, or instill hair growth (e.g. The hairline, or the side of the temples). Roll the derma roller horizontally, vertically & diagonally. Use twice a week for the best results.