Mares SXS OctopusSXS Octopus The SXS Octopus is incredibly compact and lightweight. SXS stands for Second eXtra Small and emphasizes the extreme lightness and compactness of this second stage model. Thanks to its versatility, the SXS Octopus is an excellent choice for all types of diving. In fact, with few simple operations, the user can easily change the configuration of this octopus and use it with a hose coming from the right or left side. Its slim, compact design