These are our brand gaskets, which we have been developing for years to provide a quality product without relying on other manufacturers. We have eliminated the middleman and deal directly with the manufacturer, where we can modify, enhance, and produce the quality the end user desires. If you have any questions, please call someone on our team; we will be more than happy to assist you. DK Engine Parts offers a variety of engine parts and kits for most Duramax applications and engine models. Please take a look at what we offer on our website and feel free to call us anytime with questions regarding items listed on our website. Also note that we offer more parts then what is currently listed on our website. If you do not see what you are looking for, please do not hesitate to call us. We have knowledgeable salesmen on standby to assist you with any questions you might have.