The ortlieb office black n white ql31 bag the waterproof bike briefcase with roll closure can be mounted on the right or left side of the rack it can be quickly mounted and easily taken off the rack single handed the office bag offers room for two large din a4 files size l office supplies mobile etc with the padded notebook sleeve available as extra accessory it is a perfect laptop bag up to 154ldquo two large 3m scotchlite reflectors and a reflective ortlieb logo ens