The Apidura Racing Saddle Pack is designed specifically for ultra endurance racing. The saddle bag holds seven liters and is made of a lightweight, durable and waterproof laminate coated on one side with thermoplastic and on the other side with simple polyurethane. However, in heavy rain, moisture can penetrate through the seams. A waterproof cover for electronic devices can therefore make sense. The pack doesn't wobble, offers hardly any air resistance, weighs little, is easy to fasten and the contents are also quickly accessible so you don't lose any time.