A flipper device that provides a swimmer with functional use of the flipper when fully assembled, and easy, convenient use of same when the swimmer desires to walk in the flipper. In embodment, the flipper device includes a fin positionable in (i) a swimming orientation in which the fin is configured to aid a swimmer in moving through water, and (ii) a storage orientation in which the fin is configured to be stored differently than in the swimming orientation, wherein the fin is constructed and arranged to be (a) at least partially collapsed in size to a side of the fin when converted from the swimming orientation to the storage orientation, and (b) secured in the storage orientation while collapsed in size to the side when not being used by the swimmer.

A swim fin comprising an interchangeable blade having at least two longitudinal tabs along the longitudinal perimeter edges thereof, a shoe provided with at least two longitudinal members which extend forwards from the two opposite sides of the shoe, each of the longitudinal members having a longitudinal groove for a removable engagement with a corresponding one of the tabs, wherein the longitudinal groove extends up to a front end of the longitudinal member, wherein each of said longitudinal members has a front terminal made of a more rigid material than the remaining part of the longitudinal member and configured for a shape and force coupling with a corresponding one of the tabs.

A diving fin system is provided. The fin system includes without limitation a collapsible, leg mounted diving fin. The fin system includes a first section mounted to lower leg and a second section and a third section that can collapse up to and around the lower leg. When collapsed, it can have a very low profile such that it looks like a slightly wider version of the calf area of the leg. It can be also be a three-piece deploying fin, wherein the first section is maintained coupled to the lower leg, the second section slides and rotates to couple to the top of a foot and the third section rotates away from the second section to form the fin blade for use in diving, such as scuba diving.

An aquatic propulsion device to be worn by a swimmer includes a first portion to be securely attached to the leg of the swimmer, which includes a bearing part having an inner face shaped so as to bear on the tibia of the swimmer and an outer face opposite to the inner face; a second portion including a first foil and a foil support, the first foil being secured to the foil support and the foil support enabling rotational articulation of the second portion relative to the first portion according to a first axis so as to make the device alternately switch from a deployed configuration into a retracted configuration.

A walkable swimming flipper includes a foot portion with a foot pocket and opposed sides, each side having a pivot joint. A fin portion with a fin tip and fin base includes first and second supports with corresponding hinges rotatably coupled to the pivot joints, enabling rotation between swimming and walking positions. At least one lock secures the fin portion in either position. Locking mechanisms include a twistable knob that inserts a tab into a locking hole near the fin base or a flange integrally formed with the foot portion. First and second buckles on the sides accommodate an adjustable heel strap.

Embodiments of footwear to optimize propulsion while swimming in the water and walking on land, in particular, amphibious footwear capable of duty on land and in the water as well as versions that are optimized for predominantly use in the water for swimming. The exoskeleton amphibious footwear reduces metabolic demand of walking and swimming while also improving gait speed and swim speed. This is accomplished by assisting plantar flexion during land mode, and assisting dorsiflexion in water mode.