The Ku Peltier Radiator is the secret to this neck AC device. With the 0.9 x 0.9 inch Ceramic semiconductor radiator built-in, the COOLIFY neck air conditioner only needs to cool the back of your neck to refresh your entire body in seconds. The semiconductor cooling plate quickly exchanges heat energy and transmits coldness to the skin, resulting in a noticeable decrease in body temperature by 18°F in just 3 seconds! 3D Airflow Design features 36 air vents that offer an immersive cooling experience. The upward vents blow cool air towards your face, while the downward vents prevent discomfort from long-term wear by cooling the skin on your neck. patented Air Duct, a 5000 RPM High-Speed Motor, and a 41 mm Super Wearable Air Conditioner. Bladeless neck fan is maximum comfort and convenience. Its bladeless design and metal honeycomb mesh ensure safety and prevent hair tangling. The soft silicone material is adjustable to fit any neck size. Weighing just 350g and operating at a whisper-quiet 31dB. -impressive battery life, lasting up to 2-4 hours in cooling mode and 3.5-8 hours in fan mode, depending on the selected setting. -three adjustable settings to optimize battery usage. -come equipped with a Type-C charging cable that only takes 2 hours to fully charge The COOLIFY personal neck fan comes with a specially designed space capsule case, providing a sense of tech and mystery. Imagine the surprise moment when your beloved one receives this neck cooler as a gift.