A dermaroller is a small device that can be rolled over the skin. The device contains tiny needles which pierce the epidermis. Dermarollers are used for various dermatological purposes, including but not limited to combating wrinkles, acne, scars and stretch marks. Dermarollers can also be used for stimulating hair growth and improving the absorption of topical lotions into the scalp. An excellent addition to your current hair growth treatment.