What is the purpose of the eight inch...
What is the purpose of the eight inch zippers in the armpits?
Hey Barbara, they are vents... unzip them when hot without having to unzip/take off the jacket...
Pit zips are for when you are exercising to let perspiration and heat out of the jacket. Typically waterproof shells have them under the arm pit to allow air ventilation in an area where rain cannot access the interior of the jacket.