CrossFit 646 is a CrossFit affiliate and strength and conditioning gym in Tucson, Arizona. The gym offers CrossFit classes that include warm-up work such as mobility, flexibility, calisthenics, and skill development, along with introductory sessions that teach foundational movements and build confidence for regular classes. It also provides programming and coaching for athletes interested in CrossFit competition, including accessory workouts to support local, regional, and CrossFit Open events, with an emphasis on community and long-term fitness.