PHYSICAL COLOR CHANGING LENS: In indoor environments without direct sunlight, the lenses of these Bluetooth glasses remain clear, suited for work or study, you can simultaneously enjoy music or take calls. Outdoors, the lenses gradually tint in response to sunlight: appearing light gray on cloudy days with low light, and deepening under bright sunlight, effectively blocking UV400 rays. (Note: Lens color changes may be less noticeable in less intense sunlight.) INTELLIGENT AND CONVENIENT: These Bluetooth sunglasses have been upgraded to make them more convenient to use: OPEN the temples and the sunglasses will automatically TURN ON (NOTE: the default volume is the highest volume after turning on, please adjust the volume by yourself); CLOSE the temples and the glasses will automatically TURN OFF. LIGHT AND DURABLE: These glasses are lightweight and comfortable. With high elasticity anklets, they are easy to adjust, can better fit the shape of your head and suitable for many face shapes. High-quality smart glasses are powered by a double-leg battery capacity. Standby time is about 6.3 days, phone call time and music play time are about 4-5 hours. It can be fully charged through magnetic charging in about 70 minutes, which is convenient for you to use. SMART ONE-HANDED OPERATION: The sunglasses temples are equipped with sensitive touch sensors, which allow you to fulfill various commands. Once click to pause or play music, or answer or hang up the call. Double click to switch songs. Long press 2s to adjust the volume. NOTE: Please check the manual for MORE and DETAILED instructions! MEET MULTIPLE SCENE NEEDS: These color-changing lens glasses are no longer limited to outdoor scenarios, but can also accompany you during indoor activities. Whether you are indoors working, reading, in a meeting, playing games, or outdoors traveling, driving, walking, fishing, our Bluetooth Smart Glasses can accompany you and enhance your experience by playing music or providing voice assistant operations. Indoors or outdoors, they deliver clear vision and a unique experience.