The 7-round is a favorite for shading. Remember, the more needles in a configuration the more resistance you have in the skin. So, the needles tend to work more shallowly and this is often a good thing. I like this needle for MICRONEEDLING scars around the ears and upper eyelid scars... all from plastic surgery. There are 15 cartridges in this box of the 7-point round needle configuration. All Certificates of Sterilization are kept on file for your safety.