Freedom Aerial Dog Runs Super Heavy Duty chain tree tie for BIG dogs ranging in weight between 65 and 150 pounds. This is one component (Attachment Mount) of four total necessary to build a complete aerial dog run. The other three components are the overhead cable, the lead line and the attachment mounting hardware for the second installation point. Chain tree ties are quick and easy to install using nuts bolts and washers to create a loop or ring around the tree that the overhead cable can be secured to. When ordering, measure the length around the tree and add a minimum of 12 inches to allow the chain to overlap itself to enable installation of the nuts, bolts and washers. This type of installation onto a tree can be intrusive as the chain will dig into the tree however it does not require a hole to be drilled. The tree must be tapered or there must be a branch or notch in the tree to prevent tree tie from falling down the trunk of tree. Can be purchased as a stand-alone item to replace an existing tree tie or grouped with other components to build a completely customized Freedom Aerial Dog Run that fulfills the requirements for any application. Recommended for BIG dogs between 65 and 150 pounds.