https://www.amazon.com/underbelly-Material-Underbelly-Permanent-Waterproof/dp/B09HJVTLSJ/ref=sr_1_4?hvadid=410020253517&hvdev=c&hvlocphy=9027230&hvnetw=g&hvqmt=e&hvrand=9587008571766075988&hvtargid=kwd-112564189453&hydadcr=7471_11110521&keywords=rv%2Bunderbelly%2Btape&qid=1681049920&sr=8-4&th=1Order this. Then once you get it, poke a small hole in the underbelly in the center. IF you have any water accumulation let it drain out. Then seal the hole with a small square tab of the underbelly tape. IF you have any water, IT HAD to come from someplace. The previous owner may have had a leak and fixed it, but did not drain the water out. Doug
