Have trouble deciding which extra t shirts to take along or whether you should take two pairs of shoes or threeswitch to ortlieb the worlds largest waterproof bike bags have space for everythingthe back roller pro plus is the xl version of the popular back roller plus touring bag with a volume of 70 liters per pair it offers almost twice as much stowage space its also the first ortlieb back roller with an additional front pocket although not waterproof the pocket is unusually practical of