An adjustable fin for use on a surfboard, the adjustable fin comprising: a base which comprises a mounting means for mounting the adjustable fin to a surfboard, and a member extending in a direction contrary to the mounting means. The adjustable fin further comprises a fin section comprising two outer fin surfaces which meet at a leading edge and a trailing edge; an underside surface comprising an opening to an internal cavity, the internal cavity configured to house the member and enable slidable movement of the member in a direction towards the leading edge or the trailing edge; and a locking means that is manipulate and which projects into the internal cavity, wherein the locking means can releasably couple to the member at one of two or more locking positions thereby preventing slidable movement of the member. The fin section can be adjusted relative to the base by manipulating the locking means to uncouple the locking means from the member at a first locking position, slidably move the member through the internal cavity, and releasably couple the locking means to the member at a second locking position.

A system for launching and recovering an underwater vehicle (18), which system comprises a crane (16) and a storage location for at least one underwater vehicle (18), wherein the crane (16) is attached to the bottom of a first container (12) and the storage location is provided in a second container (14), said first container (12) being arranged on the second container (14) during an operation of launching or an operation of recovering.

A sportsboard locking device that fits into the horizontal channel of the standard finbox, the device having a housing with an internal slot, an extending flange and a lower club foot, the device further having a slider with a lever on top, the slider capable of sliding down through the inner slot of the housing and into the horizontal channel such that the lower club foot on the extending flange is locked into place within the track underneath the horizontal channel.

An extendable hull system movable between a mono-hull to a multi-hull configuration is provided so as to take advantage of both types of hull designs depending on the boating conditions. The extendable hull system provides a center hull portion and two side hull portions, each with separate planing surfaces in an expanded multi-hull configuration, and providing a shared planing surface in the contracted mono-hull configuration. The extendable hull system provides a pivotably connected railing system along a periphery of the side hull portions for moving to a deployed configuration providing additional walking surface. The extendable hull system provides a retractable awning movable between positions for covering the mono-hull and the multi-hull configuration.

The invention allows setting up floating platforms comprising an elongated central body (1) from the lower portion of which legs (2) come out intended to fix the platform to anchoring elements arranged in the sea bed (5). The vessel comprises: a) a longitudinal through groove (4) up to the vessel bottom, and leaving part of the vessel bow (5) open; and b) a plurality of slots (6, 7) placed at the bottom of the vessel, wherein the groove (4) and the slots (6, 7) are configured both in dimension and in shape in such a way that they fit in at least some of the legs (2), so that the legs (2) can be inserted, at least partially, in the slots (6, 7) to attach the platform to the vessel.

A fin box that accepts fins from multiple different fin box systems. The fin box can include a fin box body and a detachable insert. The detachable insert can be inserted within and secured to the fin box body in multiple positions where each position enables one or more different types of fins to be used with the fin box.

A watersports boat includes a hull having an underside that defines a running surface that contacts water when the hull moves therein. The running surface includes a planing mode trailing edge and a pre-planing mode trailing edge. An aft running surface section of the hull includes port and starboard recesses that extend from a respective step at a forward end thereof aft to a respective aft edge thereof. The steps form the planing mode trailing edge where water disengages from the aft corners of the aft running surface section when the boat travels in planing mode and the aft edge of the recesses form the pre-planing mode trailing edge where water disengages from the aft corners of the aft running surface section when the boat travels in pre-planing mode.

[Problem] The present invention relates to a surfboard fin attachment structure. More specifically, the invention addresses the problem of providing a surfboard fin attachment structure, which is capable of detachably attaching a fin to a surfboard, wherein the attachment structure is capable of tight fitting even though easy attachment and detachment are possible and allows fitting without fin shaking or shuddering. [Solution] A surfboard fin attachment structure comprising: pin insertion recesses on both side surfaces of a cavity and, continuous therewith, grooves that continue in the depth direction of the cavity, said grooves extending from a given depth towards the back of the direction of board movement in the longitudinal direction of the fin box; and, on both sides of the fin attachment base, pins corresponding to the pin insertion recesses. The fin is attached by aligning the pins with the pin insertion recesses and inserting the attachment base, and after insertion, moving the fin towards the back of the direction of board movement.

A fin with a unique design for use with surfboards.

A fin with a unique design for use with surfboards.