Abbreviated as RT, it is a brand of Matsumoto Kiyoshi Drugstore in Japan, which is specially developed for mature women, and its main effect is moisturizing. RT's lip serum has made a good name in recent years, and it has always been the most prominent position on the counter of Japanese pharmacies, and it is also in the ascendant in China, and fashion blogger Rebecca once recommended it. Like Obagi, this lip serum is also mainly moisturizing, but weaker than Obagi, but it has a higher moisturizing level than many lip balms, and the overall moisturizing effect is better. In addition, it is also added with the anti-wrinkle ingredient tretinoin tocopherol, which can prevent the appearance of lip lines and maintain the elasticity of the lips. It has a gel-like texture, good spreadability, non-stickiness, and outstanding freshness, and RT Lip Serum can be used as a lipstick base or as a lip mask like Obagi. On the packaging, it has a patch on the body of the bottle to ensure that it has not been opened before use, and when opened, the design is somewhat similar to that of lip gloss, and it comes with a lip brush. At present, this product is available in many drugstores in Japan, and the price of 8 ml is about 75 yuan.