I've only tested the functionality to avoid any issues! I'm open to a small price reduction... A Peltier-effect water-cooling vest that circulates cold water without the need to prepare ice! It's a rather interesting vest with potential. Let's definitely get through the still-hot summer! - Model Name: Medy-Aid Icing Gear Vest 2 - Size: M-LL (Chest: 86~105cm) - Cooling Time: 5 hours - Temperature Range: Usable in environments of 35°C or higher - Function: Peltier cooling function I'm looking forward to your comments ^_^ Of course, you can buy it immediately ^_^ Thank you for looking.