How does the external baffle work?
As wind hits the external baffle it is forced over the ridge vent creating a low air pressure above the vent openings on the ridge vent. This low pressure above the vent openings allows air to be pulled from the attic through the exhaust vent — enhancing the vent's performance. There's a special name for this phenomenon. It's called the Bernoulli Effect and it's the same principal that gives lift to an airplane.