Dive computers are an essential part of any professional diver's equipment roster. Unlike scuba diving itself, these dive computers have evolved quickly and tremendously well. The Mares Icon HD is pretty much the coolest of them all. Besides having a full-color LCD screen, this computer records up to 50 logbook dives. The Icon HD also uses a "Reduced Gradient Bubbles Model" algorithm which takes into account the possibility of microbubbles without compromising dive time. Pretty slick.