Usage instructions: please simply place the device on your affected nail and long press the power switch, then the light starts flashing, the blue light and invisible super pulse light work at the same time. This device turns off automatically after 7 minutes of treatment. Please use this device daily and at least once a day. Rechargeable and battery efficiency: a USB cable is included, once fully charged, it can last for days. No replacement battery is required. Practical and portable: super light and compact, fits comfortably on fingers and toes of all sizes. It is easy to carry and can be used anytime and anywhere. Effective and scientific: With a simple session of only 7 minutes daily, you can see a great result within a few weeks. It is healthy and reliable, and no complicated procedure is required after treatment. Safe and reliable: KTS nail treatment device with highly effective and natural light therapy function is pain-free, without risk and side effects. The 470nm blue light can kill the bacteria, keep the nail clean, while the 905nm super pulsed invisible light can interact with the iron ion in the hemoglobin and enrich the affected area with oxygen to achieve the treatment effect.