The Ortlieb Bike Packer Classic has received praise for its mounting system, materials and functionality. The material is very sturdy and completely waterproof. Thanks to the "flap top" structure, thye are easy to use during the day when you need to get something out of the pannier in a hurry. - Welded seams - Quicklock and well adjustable attachments - easy to use with little effort - The panniers are attached via hooks that open simply by lifting the handle - Cord cinchable mouth and flap - Flat inner pocket with zipper - The volume of a pair is 40 liters - Quick Lock 2.1 mounting system - High quality reflectors o front and back - 5 year guarantee - Made in Germany Weight and volume refer to a pair of panniers. The price includes a pair of panniers, by moving one item to the shopping cart you receive two panniers.