I bought one of the large 3 knotted ropes years and years ago and it has sustained multiple bouts of tug of war with several large dogs. They go crazy for it, and will instigate play with one another by taking the rope bone up to the other and shaking it in their face until they grab the other end. Then the tug is on! They will tug for a half hour at a time and this thing still shows minimal damage. It's not meant as a chew toy and I don't allow my dogs to chew on them but if used as a tug toy, it can last years.