□-----■---Product Description---■-----□ Persistent Cooling with the Latest PCM Cooling Technology: This cooling pad for backpacks reduces back sweat during summer outings, commutes, school commutes, and shopping trips. The phase change material (PCM gel) adopted from NASA technology freezes naturally below 28°C, providing sustained cooling when combined with a cool backpack. It keeps you cool for 60-90 minutes in an environment of 25-35°C (more energy-efficient than conventional cooling materials). Using the physical phase change principle, like "ice that doesn't melt," it keeps your back cool and prevents body odor. Safe for use by adults and children. Designed for safety as a heatstroke prevention product for both adults and children. Versatile Installation for All Scenes: From preventing back sweat during commutes to preventing heatstroke during elementary school commutes, cooling during outdoor activities (fishing/fireworks displays), and multi-use for car seats/strollers. When attached to a backpack, it functions as a cooling pad; when removed, it quickly transforms into a cool cushion or cooling pillow. It shuts out the heat on your child's back during their commute to school and prevents heatstroke with natural cooling that eliminates the risk of frostbite. A multi-use design that balances cooling effects and heat countermeasures. Ergonomic × Lightweight Design: Optimized 22 x 28 cm size for backpacks (compatible with all types of backpacks, from school bags to outdoor backpacks). The 3D shape fits the back and provides a cool, close contact. The ergonomic back fit shape + independent filling structure maintains a flat fit even after repeated use. Ultra-lightweight design of 6mm thickness and 190g (50% smaller than conventional products) for excellent storage. The back pad with ventilation holes promotes cool air circulation, preventing condensation and improving breathability. Adjustable clips for easy installation in 10 seconds, even for children. Safe and Durable with High-Quality Materials: Uses German-made biodegradable PCM (TÜV biodegradation certified). The 3-layer barrier structure completely prevents frost and condensation. Passes the JIS S 4057 standard's 3x (30,000 times) pressure resistance test. Medical device-grade flexible TPU material realizes natural freezing below 28°C (zero risk of frostbite). Colorfast ink technology with less than 0.1% color fading after 1000 washes + antibacterial treatment thoroughly suppresses mold/odor. Thorough Guarantee of Japanese Quality Control: Integrated production at our own factory certified by ISO9001. All products undergo inspection before shipment using a 3D measuring machine. Free exchange in case of size mismatch, and a 365-day free replacement guarantee in case of liquid leakage. We promise safe use in all situations with a thorough inspection system based on Japanese quality control standards. $$480 1-2