Freediving equipment consists of decades-long knowledge, great scientific discoveries and 21st century state-of-the-art technology. Concentrated in a gear bag, freediving equipment comprises just a few items which the freediver must wear, with each item intended to augment his physical abilities to a much higher level. Understanding the characteristics and operation of each part of the freediving equipment is crucial for freedivers, and their progress in freediving technique largely depends on it. A second, vital rule in the selection of freediving equipment, is that it must individually fit the needs of the particular diver, and its selection must be based on every diver's personal needs. Even today, this remains the greatest difficulty when selecting equipment: it still is a piece of clothing, which must individually fit its owner's body, while at the same time offering all functional elements required by the diver. So, in our discussion on equipment, we rely on two principles: First, there is no ideal freediving equipment for all divers in general, but there is ideal equipment for each diver and each desired type of freediving. Second, even the best personal equipment, in terms of design and quality, will be rated as to its functionality by what we eventually do in the water! This book aspires to aid in this effort, i.e. teaching freedivers how to select and evaluate the equipment before purchasing it, and then rating it and classifying it in the water. Even today, the appropriate knowledge is still the most precious gift when choosing freediving equipment, because, even in our time of abundance, the selection of suitable equipment for an activity as specialized as freediving remains a science in itself! The book follows a specific method to solve the "equipment problem" for every diver at any level of experience: 1. It describes the materials and the designing principals for each item of the equipment. 2. It describes the requirements in functioning underwater. 3. It names "the rules of the game" in selecting every item of the freediving equipment by writing down the different requirements of every level of training from each item and the possible personal requirements a specific diver could add to fit his personal needs. Selecting the freediving equipment should be an interesting and enjoyable experience, both at the stores and in the water, and this is the goal of this guide: to help all levels of freedivers discover new ways to choose, test and grade their equipment and make their personal, high performance and complete freediving gear!