This is the same epoxy we use in all of our projects and is incredible stuff it is great for filling medium to large size holes, cracks, and adds structural integrity. This is a slow curing epoxy and works excellent on making rivers, and doing large fills as it has a much lower risk of cracks and bubbles. Very easy to use, it is a simple 2:1 ratio and is packaged in three one gallon jugs. Oak city customs is proud of its brand and if there are any issues, concerns, or just general questions about how to use our products please reach out for a response within 24 hours. This item is made of epoxy, plastic and resin.