The adult bullfrog does about 80% of its breathing through its skin. Why are we pointing that out? Well, we just couldn't find a better way to put into perspective the breezy, aired-out feeling we get when wearing the Gore Bike Wear Oxygen FZ Jersey. So imagine skin-breathing, pedal-pushing bullfrogs (that would be a sight, wouldn't it?).But enough of frogs?the Oxygen FZ is clearly designed for serious cyclists of the human variety. It has a tight, ergonomic fit due to the nylon/spandex blend in the fabrics; however, maximum ventilation is the name of the game here, so it incorporates large mesh inserts under the arms, in back, and at the nape. The full front zip with semi-lock slider gives unlimited temperature control. An elastic gripper on the hem ensures that the jersey won't ride up when you're in an aerodynamic position. The three-compartment back pocket gives you plenty of room for your gear, and a zip pocket provides security for the items you really don't want to wiggle out and get lost, like keys or cash. A reflective logo on the front and reflective piping on the back enhance your visibility in fading light or adverse weather. The Gore Bike Wear Oxygen FZ Jersey comes in sizes Small through XX-Large. It's available in five color options: Black/white, White/black, White/citrus green, White/pool blue, and White/red.