Flex-Mend Underbelly Tape Adhesive cloth is a strong repair fabric made of the same material as the Polyethylene Underbelly. The advantage of this tape is that it has a strong adhesive backing to the material that can be applied directly to problem areas. The reason this tape is a top-use product for this application is that most tapes have a difficult time adhering to the Polyethylene cloth. Duct tape and other iterations of "strong" adhesive cloths will stick, but only temporarily. Instead of making frequent repairs to your underbelly, use a more permanent solution such as Flex-Mend.
 
Polyethylene Underbelly is a stout cloth material that has been used in the manufacture of mobile homes for decades. Since the 1980's OEMs have used this black cross-hatched fabric, reminiscent of the same material you would find in a tarp (standard use, not construction grade). This cloth is utilized in the protection of mobile homes, trailers, sheds, RVs, homes, and other residential applications. It's flexible, easy to install, tear-resistant, and is water repellent so that you will see little to no water encroachment in your vehicle. While this material is incredibly durable, it will from time to time become damaged. Whether by tearing, natural wear, or another incident, this fabric can break down. You will need a qualified product to apply to your damaged areas of underbelly cloth in these instances. RecPro now offers such a product.
 
Flex-Mend is a front-of-industry mending tape that not only matches the texture and looks of bottom under-fabrics but is a permanent fixture once correctly applied. The specially-engineered adhesive applies easily and the woven poly-film will become a seamless part of the original fabric. Once it is used, almost immediately it becomes nearly impossible to remove without destroying surrounding structures.