Magnetic Flap Design: The ROCKBROS bike frame bag features a powerful magnetic flap design with built-in strong magnetic foils. This simple clamshell mechanism allows for quick and easy access with one hand. Durability and stability: The top tube bag is constructed from extremely durable materials and reinforced with PP panels for excellent durability and structural integrity, even when empty. It withstands daily wear and tear and provides stable storage for all your adventures. Waterproof: Thanks to advanced waterproof materials and seamless high-frequency welding, this bike bag prevents water from seeping in, keeping your belongings safe in inclement weather. It's the perfect companion to protect your ride from the rain, whether it's your daily commute or a long ride. Comfortable cycling: The slim, streamlined design of the ROCKBROS bag minimizes air resistance and prevents your legs from getting in the way while riding. Ride without the worry of a bulky storage compartment, so you can focus on your performance. Easy Installation: The bike bags feature two highly adhesive, non-slip Velcro straps that securely hold them to your bike frame with minimal effort. The Velcro straps can be cut to your desired length to ensure a perfect fit for any bike configuration.