Whenever I go out in my leathers, I get questions. One of the more frequent questions is – “What is that hump for?” The hump on the back of motorcycle leathers serves a few purposes. Most are at least partly vented using perforated leather similar to the rest of the suit. A suit made by Dainese, the Aero Avro P., has space for a water bag. My suit, a Dainese Laguna Seca, has air vents in the hump to allow better cooling when crouched on the bike. No matter how the suit is ventilated, the hump’s greatest use is aerodynamics. The hump helps air flow better over the body and the helmet. This also makes it easier for the rider to stay in the crouched position longer as the air flow helps hold the head up. My personal preference is for suits with humps. I just find them more interesting to look at and wear.