Our dog is extremely hyper, we use the pack so that she can add weight and actually tire out during a walk. we usually walk about 6 miles at a time and after three or four walks her pack started ripping! Both pockets now have holes and have been patched several times! This pack was great at first but now it's useless because even if we only use it to hold our keys we have to constantly check to make sure they haven't fallen out.