✨Brand New✨ Color: Blue 【Latest PCM Cooling Technology for Sustained Cooling】 As a cooling pad for backpacks during summer outings, commutes, school trips, and shopping, it reduces back sweat. The phase change material (PCM gel) adopted from NASA technology freezes naturally below 28°C, achieving 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 adults and children. As a heatstroke prevention item, it's designed for safety for both adults and children. 【High-Quality Materials for Safe and Lasting Use】 Uses German-made biodegradable PCM (TÜV biodegradation certification). A 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 achieves 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. 【Ergonomic Design × Lightweight Design】 Optimized 22 x 28cm size for backpacks (compatible with all types from school backpacks to outdoor backpacks). 3D shape that fits the back for a cool, close fit. 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. Back pad with ventilation holes promotes cool air circulation, preventing condensation & improving breathability. Adjustable clips for easy installation in 10 seconds, even for children. #Anno'sShop