Review on Black POR-15 Patch - 4 oz Filler & Seam Sealer with Ultimate Adhesive Properties - Repairs Holes, Cracks in Steel, Wood, and select Plastics - Reinforces Weakened Metal by Sam Sergio

Suitable for filling small holes like weld burn. It might be a good way to reinforce rusty old welds, but it's better for smaller jobs and I wouldn't use it as regular seam sealer. I probably wouldn't buy it just to fill holes that could be filled with lime grout, window welds or traditional seam sealer, limiting its use to damaged old panel welds. In this case, be sure to wear gloves. This material will stain your skin for at least a week.