Swim fins have been used for a long time and have a unique purpose for swimmers. Fins are used for many swimming activities that many people cannot enjoy swimming without them. For such swimmers, fins are used for many things such as diving, burning calories or practicing new swimming techniques.
fins are used to help do front crawl, backstroke, butterfly, and even breaststroke. when swimming in the ocean they help many swimmers to protect their feet in the ocean from reefs, and other marine life.
they give you propulsion and support your legs while practicing swimming drills and help kicking sets to provide a good leg workouts.
and overall they can be used by anybody who want to enjoy swimming for those who are not a particularly good swimmer.