I got these free. The previous owner cut off the luggage straps. I removed the vinyl cover to those straps and found I could tear it with my fingers. The outside is vinyl and the wheel side
is hard plastic sewed to vinyl side and bottom. This will be very difficult to repair. The bags have a weight limit of 5 pounds each side. Don't buy these tough leather ones may be tough enough form bicycle use. The shape clears the brakes nicely and also the axle nuts. Also they are stiff enough that I'm not worried about them getting into the spokes. I think these are the 12 inch size. My 15.6 inch computer won't fit inside.