Our stainless steel roller ball inserts are good for 16-tooth essential oil bottles, providing a smooth and efficient application. These roller balls are designed to fit securely, ensuring no leaks or spills. Ideal for aromatherapy, these inserts allow you to create your own blends and enjoy the benefits of essential oils on the go. Simply insert the roller ball into the bottle, and you're ! Features -Color:Multi -Material:Pp,stainless steel -Size:2.10X1.20X1.20cm/0.83X0.47X0.47in -Versatile use: suitable for various settings such as home, office, and spa, these roller ball inserts are good for different environments and can be reused multiple times. -Smooth rolling: the roller glides smoothly and dispenses oil evenly, allowing for better control of the oil amount at the top, ensuring no leaks. -Easy installation: simply take a roller and insert it into the bottle neck, push it flat into the bottle, screw the cap on, and tighten. installation is complete. -Leakproof design: the essential oil roller can into the essential oil bottle, preventing leaks and allowing for easy removal and reuse as needed. -Transformative inserts: our roller top inserts can instantly convert your spray oil bottle into a rollon applicator, ideal for thicker oils, diluted oils, or rolling oils Package list: 20pcs essential oil bottle roller ball