Durable 3 in 1 bike bag with practical design - Material and protection: Made from 1000D polyester with a waterproof PVC layer on both sides. This bag is tear and wear resistant, heat resistant, and helps protect your items from rain and dust. - 3 in 1 versatility: Includes two single sided shoulder bags and one backpack. Each piece can be used independently for flexible carrying options or combined for extended capacity. - Easy installation: Quick release mounting system fits most rear pannier racks for fast on and off. - High capacity and dimensions: Backpack 19.4 in L x 12 in W x 5.8 in H. Side bag 11.7 in L x 6.25 in W x 13.7 in H. Fully expanded to hold more when needed. - Compatibility: Suitable for most standard rear racks and cycling setups. - Use scenarios: Daily commuting with a laptop and lunch; weekend bike trips with extra clothing and tools; grocery runs or errands requiring compact organization and quick access. - Why it helps: Keeps gear organized, protects essentials from weather, and reduces the number of bags you carry by providing multiple independent options in one kit.