oelheld U.S. introduces AquaTec 7539. Budget-minded operations will be particularly pleased with this new, customer-driven, value-priced, versatile, semi-synthetic metalworking fluid. By listening to their customers and developing new technologies, oelheld U.S. has been able to produce with AquaTec 7539 a product, which provides lower odor, lower cost, and improved sump life compared to other value-priced, general-purpose semi-synthetics.