micro needle screw cartridge replacement for dr pen derma pen micro-needling pen 12 pin / 36 pin / nano tattoo needles

derma pen needle cartridge uses a knead rod inlayed with numbers of needles, combining with functional nutrition liquid, regularly rolling in the places which needed to cure. it can puncture more than 300,000 micro vessels on the epidermis within five minutes, forming an efficient nutrient delivery system between the epidermis and subcutaneous tissue. then the nutrition liquid can entry into skin effectively.