🟢 Product Description This neck cooler naturally solidifies at approximately 28°C, providing a comfortable cooling effect around the neck. It can be reused repeatedly. When it becomes soft in warm environments, placing it in a cool indoor space (such as an office or café with air conditioning) will help it harden again. Because it solidifies at 28°C, it can be re-cooled easily without electricity or water freezing. 🟢 How to Use Place the product flat in a refrigerator for about 20 minutes, or in a freezer for at least 5 minutes until the inside hardens. It can also harden in water below 28°C; lower temperatures make it solidify faster. Wear it around the neck after it becomes solid inside. It is reusable. 🟢 Features Solidifies naturally at around 28°C Reusable cooling neckwear No electricity required Can be re-hardened in cool indoor environments Lightweight and easy to use 🟢 Materials Outer Layer: TPU Filling: PCM 🟢 Size cm Size Width × Height (cm) Inner Circumference (cm) M 14 × 16 cm 34 cm L 15.5 × 18 cm 39 cm inch Size Width × Height (inch) Inner Circumference (inch) M 5.51 × 6.30 in 13.39 in L 6.10 × 7.09 in 15.35 in 🟢 Important Notes Do not use for purposes other than intended Do not ingest internal material Do not use while sleeping Do not twist, damage, or apply excessive force If damaged and contents leak, stop use immediately and wash with water Not a traditional ice pack Slight deformation may occur due to repeated solidification, but this is normal Wash with water if dirty Store flat in a cool, dry place Keep out of reach of children Do not place near fire or heat sources Stop use if size does not fit properly