Abstract: A method of coupling a boot toe body to a fin apparatus is disclosed. The fin apparatus includes a fin body coupled to a boot coupling body. The method involves connecting a first boot connector on a first end of the boot coupling body to a first complementary boot connector on a top side of the boot toe body, and connecting a second boot connector on a second end of the boot coupling body to a second complementary boot connector on a bottom side of the boot toe body. Boot toe bodies, fin apparatuses, and systems including the boot toe bodies and fin apparatuses are also disclosed.

Abstract: A first flipper has a base, a deformable fin connected to the base, and a first spreader that imposes a first force on the fin that causes the fin to spread in response to relative movement between the first spreader and the fin caused by a first longitudinal deflection of the fin relative to the base. A second flipper has a fin and a foot coupling portion connectable to a foot holding portion of a boot to couple a foot in the foot holding portion to the flipper. A first system includes the flipper and the boot. Methods of using the flippers, the boot, and the system are also disclosed.

Abstract: A method of coupling a boot toe body to a fin apparatus is disclosed. The fin apparatus includes a fin body coupled to a boot coupling body. The method involves connecting a first boot connector on a first end of the boot coupling body to a first complementary boot connector on a top side of the boot toe body, and connecting a second boot connector on a second end of the boot coupling body to a second complementary boot connector on a bottom side of the boot toe body. Boot toe bodies, fin apparatuses, and systems including the boot toe bodies and fin apparatuses are also disclosed.

Abstract: A first flipper has a base, a deformable fin connected to the base, and a first spreader that imposes a first force on the fin that causes the fin to spread in response to relative movement between the first spreader and the fin caused by a first longitudinal deflection of the fin relative to the base. A second flipper has a fin and a foot coupling portion connectable to a foot holding portion of a boot to couple a foot in the foot holding portion to the flipper. A first system includes the flipper and the boot. Methods of using the flippers, the boot, and the system are also disclosed.

Abstract: A first flipper has a base, a deformable fin connected to the base, and a first spreader that imposes a first force on the fin that causes the fin to spread in response to relative movement between the first spreader and the fin caused by a first longitudinal deflection of the fin relative to the base. A second flipper has a fin and a foot coupling portion connectable to a foot holding portion of a boot to couple a foot in the foot holding portion to the flipper. A first system includes the flipper and the boot. Methods of using the flippers, the boot, and the system are also disclosed.

Abstract: In one illustrative embodiment, there is provided a boot sole system for guiding a fin, the system comprising: at least one toe sole body connectable to the fin and comprising first and second stop surfaces; a posterior sole body comprising third and fourth stop surfaces; and a transverse hinge for hingedly connecting the at least one toe sole body to the posterior sole body to permit longitudinal deflection of the at least one toe sole body relative to the posterior sole body in a first deflection direction and in a second deflection direction opposite the first deflection direction. The first, second, third, and fourth stop surfaces are positioned to restrict longitudinal deflection of the at least one toe sole body relative to the posterior sole body in the first deflection direction and in the second deflection direction. Fins are also disclosed.

Abstract: In one illustrative embodiment, there is provided a boot sole system for guiding a fm, the system comprising: at least one toe sole body connectable to the fin and comprising first and second stop surfaces; a posterior sole body comprising third and fourth stop surfaces; and a transverse hinge for hingedly connecting the at least one toe sole body to the posterior sole body to permit longitudinal deflection of the at least one toe sole body relative to the posterior sole body in a first deflection direction and in a second deflection direction opposite the first deflection direction. The first, second, third, and fourth stop surfaces are positioned to restrict longitudinal deflection of the at least one toe sole body relative to the posterior sole body in the first deflection direction and in the second deflection direction. Fins are also disclosed.

Abstract: A first flipper has a base, a deformable fin connected to the base, and a first spreader that imposes a first force on the fin that causes the fin to spread in response to relative movement between the first spreader and the fin caused by a first longitudinal deflection of the fin relative to the base. A second flipper has a fin and a foot coupling portion connectable to a foot holding portion of a boot to couple a foot in the foot holding portion to the flipper. A first system includes the flipper and the boot. Methods of using the flippers, the boot, and the system are also disclosed.

Abstract: A first flipper has a base, a deformable fin connected to the base, and a first spreader that imposes a first force on the fin that causes the fin to spread in response to relative movement between the first spreader and the fin caused by a first longitudinal deflection of the fin relative to the base. A second flipper has a fin and a foot coupling portion connectable to a foot holding portion of a boot to couple a foot in the foot holding portion to the flipper. A first system includes the flipper and the boot. Methods of using the flippers, the boot, and the system are also disclosed.

Abstract: A first flipper has a base, a deformable fin connected to the base, and a first spreader that imposes a first force on the fin that causes the fin to spread in response to relative movement between the first spreader and the fin caused by a first longitudinal deflection of the fin relative to the base. A second flipper has a fin and a foot coupling portion connectable to a foot holding portion of a boot to couple a foot in the foot holding portion to the flipper. A first system includes the flipper and the boot. Methods of using the flippers, the boot, and the system are also disclosed.