You’ve probably heard you need something between your zip line cable and the bark of your trees to prevent the cable from cutting into the bark, right? The Tree Savers are the answer. The small blocks are placed around your tree and held in place with a cam strap, the zip line cable then wraps around the blocks. The blocks are made out of heavy-duty nylon, so they are resistant to sun, rain and zip line cable. Thread your cable through the blocks or, simply wrap around the outside of the blocks and tension the cable to desired height. Features: 2 Adjustable straps (one for each tree) for trees up to 3′ in diameter 16 Sleek UV Resistant Nylon Blocks (8 per tree).