Vahn-Tech Series DOBF is a cost-effective butterfly valve solution for isolation valve applications. Providing lighter weight, smaller face-to-face, and simple quarter-turn rotary movement, a double-offset butterfly valve design is a great solution for zero-leakage isolation relative to ball valves for large sizes. With the eccentric disc designed to reduce the rubbing of the seat it drastically reduces torque requirements for actuation while extending seat life expectancy.