New - Kohree Trailer Jack Block, Up to 15,000 lbs, Sturdy RV & Camper Leveling Blocks for Travel Trailer 5th Wheels and More, Use for Any Tongue Jack, Foot, Post, or Stabilizer, RV Accessories. *Built with a high-performance polymer. To meet the load-bearing needs of the trailer, we have upgraded the internal structure. It is extreme and sturdy - up to 15,000 lbs. The professional block designed for motorhomes and trailers is much better than wood blocks or other blocks. *The top of the block is designed with grooves to enhance stability during stacking use. Side hole design for easy carrying. Come and get it. I only accept cash and thanks for looking.