hopon slacklines tree protector kit - 2 piece tree guards, 40", 51", and 63" - durable green or black non-slip felt wrap pads with velcro for outdoor use - easy install (51 inch, green) hopon slacklines a special felt wrap designed to protect both the bark of the tree and your slackline from wear and tear. velcro at the end of the treeguard makes it easy to handle and fasten, and prevents the guard from slipping during set-up of your slackline. comes as a set of two. one per tree, or for larger trees, buy two sets (one set per tree).<p><p>