The Medicube PDRN mask, specifically the PDRN Pink Collagen Gel Mask, is a popular Korean skincare item featuring salmon-derived PDRN and collagen to boost elasticity, hydration, and radiance, often transforming from pink to transparent as it works, and it's available in different versions like a night-wrapping mask with caffeine for firming and depuffing. Key benefits include firming, smoothing wrinkles, improving texture, strengthening the skin barrier, and providing a glowing, hydrated finish, with use typically involving leaving it on for hours or overnight for best results.