Freedom Aerial Dog Runs Heavy Duty lag screw eye for toy sized dogs ranging in weight between 45 and 75 pounds. Overhead cable attachment hardware. Lag screw eye with wood thread. 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. Lag screw eyes can be installed into any solid wooden object and require a pilot hole to be drilled before inserting. These lag screw eyes are made with stainless steel offering superior rust and corrosion prevention. This type of installation into a tree can be intrusive as the lag screw will penetrate the tree, however, most healthy trees will have no adverse long-term effects.