A non-sterile, hand-held, mains electricity (AC-powered) device intended to be used in combination with a micro-needle cartridge (which contains micro-needles) to create high-density minute skin punctures to stimulate tissue regeneration and improve the appearance of the skin (i.e., to treat stretch marks, acne scarring, hyperpigmentation, wrinkles, hair loss) as part of collagen induction therapy (CIT). It includes controls to allow for treatment adjustments (e.g., puncture depth, frequency); the micro-needles are not part of the handpiece, however a disposable micro-needle cartridge may be included. It is intended for clinical use by a healthcare provider. This is a reusable device.