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 Robert Prix

It's a bit pricey but it's a great product. I've used it to seal seams on a car and I've used it to join wooden railings to make the structure more rigid. The main thing is that your surfaces are clean and dry before application. This product does not level itself so if it looks clumpy it is drying out. Depending on the thickness, I've experienced drying times from 24 hours to 96 hours. This is a great product that stops leaks and actually strengthens the material. I only gave one star for the price.