The ortlieb airflex backpack will make your life lighter from the first trip the compact design and 11 litres of volume make this backpack a full featured yet sleek option it is waterproof and comes with a convenient roll closure the flex wire system has good padding to offer real carrying comfort the adjustable compression cord serves for fixing a bike helment or light jacket two outer pockets not waterproof offer space for small items which should be quickly accessible two reflectors e