Ramosu MI- Roll .5 This micro needle roller is made for trans-dermal delivery of substances for healthy skin. It consists of assembled plastic discs incorporating 340 fine super plastic micro points in eight rows. Needles and the micro needle array are firmly welded by ultrasound. The roller is connected to a plastic handle. You can use this roller as directed for the best penetration of your cosmetic products daily, such as anti-aging-serum and vitamin serum, to increase collagen production thereby reducing wrinkles and acne scarring. This high performance and reliable micro needle roller can be used repeatedly about one hundred times. Name: Mi-Roll. Mi-roll is the method by which skin can be cured to health through inducing natural wound curing process like producing 15-20 hundreds thousand of micro punctures by use of delicate micro needle thinner than hair. Scar of pimple and enlarged skin pores is affected by reproduction of collagen and rearrangement of corium tissue. It is not possible to expect its efficacy by just 1-2 times of curing but it will show its strength over several times of curing. Good for curing liver spot and freckle. Needle length: 0.25/0.5mm. Roller head size: (diameter) 20 x (width) 20mm. Medical grade and FDA approved plastic material. All cosmetic products must be used under the recommendation by doctor.