Unopened. Brand new. Developed the "M1" type, which can be used as an accessory. Including the necklace, it weighs only 30g. An air purifier so light you'll forget you're wearing it. The magnetic clasp makes it easy to put on and take off, and if pulled with strong force, the magnetic part will detach, making it safe for anyone to wear. ● Generates negative ions through plasma discharge, providing air purification. ● Generates a large amount of negative ions, 1.23 million/cm3 (more than 60 times that of a waterfall in a forest). ● Features a silent (0dB) fanless design for high quietness. Uses a neck strap infused with titanium material. ● Titanium material is incorporated into the necklace, allowing it to be used as a necklace alone. It can be worn more easily, regardless of the person or place. ● Continuous use for approximately 28 hours, charging time approximately 3 hours (when charging from an AC adapter).