How to choose BLUE Light and RED Light? Both can remove a mole, lentigo, black Acne scars, black and BLUE tattoo, Eyebrow tattoo, eyebrow microblading, and any other melanin. For Black Color tattoo, you can choose RED light and for a colorful tattoo, you can choose BLUE light. Note: the color should be deep, light color is difficult to be removed. RED light Picosecond pen is for personal home use, you can operate it by yourself . its power and effect is lighter than BLUE light Picosecond pen. BLUE light Picosecond pen professional grade and can be used for beauty salon and may need some one's assistance to operate it, you can not operate it yourself because you need to wear the protective eyes glasses, its power and effect is stronger than the RED light Picosecond pen. Blu-ray beauty pen: There are 9 light-emitting frequencies, mainly tattoos, eyebrows, various spots, RED blood, acne marks to eliminate freckles need to wear laser protective glasses (products including goggles). RED light beauty pen: It contains continuous light, high power, suitable for melanin with large operating area, tattoo, eyebrows and large enamel. The output frequency is adjustable in 3 steps. (It is recommended to start from the minimum gear position, not enough to add up.) The RED light operation does not need to wear a light-shielding mirror, the RED light will not flash, it will not affect the eyes. Functions: Mole removal, Dark Spot/ Freckle/ Pigment removal, Eyebrow Makeup Cleaning, Eye bag removal, Acne Treatment, Scar removal & More, Stretch Marks, Spider Veins. How Long will it take? To How Long will it take? To begin to see the results, we recommend using it for 2 weeks. begin to see the results, we recommend using it for 2 weeks. PACKAGE: 1 x Picosecond BLUE Laser Pen, 1 x Power Adapter, 1 x Protective Eyewear, 1 x User Manual.