Pit Zips
Pit zips are pretty self-explanatory; they’re zippers located in or near the armpits, allowing the wearer to spill some heat when things get a little warm. Ideally, they are pretty long; some of the best I’ve seen usually go from about the elbow to about the end of the ribs. They can also be called core vents, but core vents are typically in the front or lower down the side; they often function as both core vents and pockets.
