Grangers Tent & Gear Repel is a paint-on waterproofing product designed to protect tents and other items of outdoor gear and equipment from rain and stains. Over time, and with use, even the best outdoor gear will begin to lose its ability to repel water. Dirt, dust and other impurities, general wear and exposure to UV will remove much of the water-repellent finish your gear may have been treated with. Cleaning your gear can help, but eventually, it will need reproofing with a water-repellent product.