What tool is used to clean under the free edge of the nails?

The orange wood stick with cotton is the appropriate tool for cleaning under the free edge of the nails. This tool is designed with a gentle texture, making it less likely to damage the delicate skin surrounding the nails while effectively removing any debris or buildup. The cotton tip adds an additional layer of gentleness, ensuring that the process is comfortable for the client.

In contrast, while a metal pusher is also used for nail care, it's typically more suited for pushing back cuticles rather than cleaning underneath the nails, as it can be too harsh on that sensitive area. A nail file is primarily meant for shaping and smoothing the surface of the nails, not for cleaning. Similarly, a nail brush is designed for scrubbing the surface of the nail and surrounding skin rather than targeting the space under the free edge. Understanding the specific use of each tool is crucial in providing effective and safe nail care.