"Shield your tarp from metal-on-fabric damage with these Spreader Bar Tip Covers. They fit snugly over the ends of your spreader bars to create a soft, resilient cushion that prevents punctures, abrasion, and premature wear. Designed specifically for Ridgerunner hammocks using Amsteel connections. Sold as a set of 4."
 
The above wording is straight from Brandon and his team at Warbonnet Outdoors. 
 
*Included free with every new Ridgerunner hammock and spreader bar replacement set — no need to purchase separately.