Since 2010, Blue Sky® has been providing the highest quality diesel exhaust fluid to satisfied customers throughout North America. Whether in vehicles large or small, on- or off-road, Blue Sky DEF is a trusted and environmentally responsible emission-control solution for diesel-powered engine operators everywhere. Blue Sky is more than just a manufacturer of high-quality diesel ex-haust fluid. We are the DEF experts. At Blue Sky, we know that being a responsible business is about more than the bottom line. We want to do our part to help make the planet greener. That’s why we take extra steps to make sure all of our products are recyclable and that we produce little to no industrial waste.