Dual outlet-type BOV. Dual Port vents both to the atmosphere and back into the air intake. Ports with sequential timing allow quieter operation during everyday driving while getting all the benefits of a vent-to-atmosphere BOV under race conditions. They are easily converted to an entire atmospheric or full bypass unit using supplied port blanking plug. Dual Port vents both to the atmosphere & back into the air intake. Ports with sequential timing allow quieter operation during normal driving, while getting all the benefits of a vent-to-atmosphere BOV under race conditions. It fits most cars using the factory BOSCH or DENSO bypass valves. Universal