Supply Giant Pipe fittings are manufactured out of high-quality cast iron which are designed to last a lifetime. They are safe to use with gas, oil, and water. Cast iron features quiet piping, for those that enjoy peace and quiet. Fit all standard thread connections. These pipe fittings are also great for DIY projects to create your custom pipe furniture. They don't require any skills and are super easy to assemble and install.⚠ California Proposition 65 Warning: This product is known to the state of California to cause cancer, or other reproductive harm. For more information, go to www.p65warnings.ca.gov. ⚠ California Proposition 65 Warning: This product is known to the state of California to cause cancer, or other reproductive harm. For more information, go to www.p65warnings.ca.gov.