Insulated Liner (Cold & Warm Preservation) WEST BIKING cycling backpack has built-in insulated liner. Maintains drink temperature (cold in summer, warm in winter) for long-time riding comfort. Compatible with 2L Hydration Bladder Designed to fit 2L hydration bladder (A separate backpack or suit is optional). Easy to install and access water, free hands during cycling without carrying extra water bottles. Water-Repellent Fabric (Fears No Light Rain) Adopts water-repellent material, effectively resists light rain and splashes. Not recommended for heavy rain, keeps gear dry in daily outdoor scenarios. Ergonomic Shoulder Strap & Multi-Pockets Breathable ergonomic shoulder strap reduces back pressure. Multiple pockets organize small items (phone, keys, riding tools) for easy access. Lightweight & Large Capacity (10L) Ultra-lightweight nylon material (only 300g) with 10L capacity. Spacious enough for riding gear, suitable for mountain biking, hiking and leisure outdoor activities. 10L Insulated Backpack Information 2L Hydration Bladder Information Bicycle Backpack;Insulated Cycling Bag;2L Hydration Bladder Compatible Bag;Water-Repellent Bike Bag;Lightweight Bicycle Backpack;Outdoor Cycling Bag;Mountain Bike Backpack;Cycling Accessory;Bike Gear Bag;Insulated Bike Backpack;2L Hydration Cycling Bag;Water-Repellent Cycling Bag;30L Bicycle Bag;Lightweight Bike Bag;Riding Backpack;Bike Storage Bag;Outdoor Sports Backpack;Cycling Hydration Bag;Bike Accessory Bag;Leisure Cycling Backpack