This set is made of heavy duty leather.  There are built in straps on the back of each to attach to bike in different configurations and they also buckle together as a set.  The motorcycle pictured is of the bags packed and mounted.  They are nylon lined and come with nylon rain bags for each individual one.There is no damage or wear to either of them and both are in excellent condition. Each one has plenty of quick access exterior pockets for smaller items. I've had several sets and this one is the ultimate.  Best one I ever owned.  Selling because I no longer travel.