Flex oil is a popular supplement and topical treatment primarily used for promoting joint health and alleviating muscle and joint discomfort. Composed of a blend of natural oils and sometimes combined with other herbs or compounds, it is commonly used by individuals with arthritis, muscle pain, or general inflammation. This review aims to explore the composition, potential health benefits, applications, and scientific evidence surrounding Flex oil, as well as its role in complementary therapy for musculoskeletal conditions.