A pontoon boat having central pontoon located between outer pontoons. The outer pontoons are fixed with respect to the deck and the central pontoon is movably fixed with respect to the deck. The central pontoon is movable with respect to the outer pontoons and the deck between a first position that locates the central pontoon near the deck and a second position that locates the central pontoon relatively far from the deck. The central pontoon is selectively fixable between the first and second positions.

Provided is a water track marker (1) for marking a sports track, such as a water ski track, on a water surface (20). The water track marker comprises at least a first marker ejector (11) configured to eject marker projectiles (2) towards the water for creating an instant marking (3) on the water surface (20) upon impact with the water surface (20). Provided is also a method for marking a sports track and a towing boat comprising said water track marker.

A system may include an inflatable towable vehicle. The inflatable towable vehicle may include a spinner apparatus attached to a bottom side of the inflatable towable vehicle. At least a portion of the spinner apparatus may be configured to be submerged when the inflatable towable vehicle is towed in water. The spinner apparatus may include: a base configured to abut the bottom side of the inflatable towable vehicle when the spinner apparatus is attached to the bottom side of the inflatable towable vehicle; a post extending away from the base; a cylindrical tube, wherein the post may extend through the cylindrical tube, wherein the cylindrical tube may be configured to rotate around the post; and a tow rope attachment member attached to and extending from the cylindrical tube. The inflatable towable vehicle may be configured to rotate as the inflatable towable vehicle is towed.

Water walking skis and a method for boarding them, in which each ski has an elongated body with a bow end in the form of a monohull and a stern end in the form of a twin hull. The skis can be combined with a pair of poles for balance, and binding straps for binding the skis and poles together while boarding/reboarding. The deck of each ski typically has a recessed area for foot placement, and two parallel side extensions protrude downward from the deck. The side extensions, the deck, and an underside or bottom cover together form a tunnel within the ski, the tunnel having a screen-covered first opening for admitting water and a rear opening for expelling water. Traction gates are mounted within the tunnel and spaced apart therein for permitting water flow therethrough when the ski moves forward, while preventing water flow when moving in the reverse direction.

A water ski system includes an elongate ski body member having an aft end portion with a mounting face. Interchangeable tail members having an engagement face are configured to be selectively mounted to the ski body such that the engagement face of the tail member abut the mounting face of the ski body member. Attachment hardware removably fixes the selected tail member to the ski body member. The interchangeable tail members may have a variety of shapes and lengths, allowing a skier to customize the water ski to accommodate differing water ski styles, water, conditions, and skill levels.

A water ski system includes an elongate ski body member having an aft end portion with a mounting face. Interchangeable tail members having an engagement face are configured to be selectively mounted to the ski body such that the engagement face of the tail member abut the mounting face of the ski body member. Attachment hardware removably fixes the selected tail member to the ski body member. The interchangeable tail members may have a variety of shapes and lengths, allowing a skier to customize the water ski to accommodate differing water ski styles, water, conditions, and skill levels.

Structural arrangement for a water ski or underwater ski comprising essential mechanisms for significantly improving the user experience in underwater wake bodyboarding. The ski is characterized by the addition of novel and different attachable items that enable the ski to be used without a powered vehicle. The ski is also characterized in that it has various different items that can be attached to the cowling to improve the performance and comfort of the equipment, combined with a personalized steering system and an essential safety system, providing a model that is unique on the underwater ski/water ski market.

Provided are a sliding instrument having a low frictional resistance to the snow surface, the ice surface, or the water surface and having excellent sliding performance and a method for manufacturing the sliding instrument. A sliding instrument to slide on snow, ice, or water includes a sliding surface (1) to come into contact with the snow surface, the ice surface, or the water surface, and the sliding surface (1) has a surface roughness Ra of 1.0 m or less. A method for manufacturing the sliding instrument includes polishing a sliding surface (1) using a polishing composition slurry containing abrasives to make the sliding surface (1) have a surface roughness Ra of 1.0 m or less.

A fin for a slalom water ski includes a planar body with a convex leading edge and a slot proximate such leading edge. The slot has an arcuate front or leading edge and a wavy rear edge defined by alternating crests and troughs or projections which allow the fin to be smaller without compromising its ability to support ski acceleration. The smaller size allows the ski to be turned more easily. A line of small holes extending in a row proximate the leading edge of the fin body can achieve the same result.

A wakeboard binding assembly in which the upper may be directly connected to the base plate without additional adhesives, stitching, or fasteners thus facilitating the assembly, removal, modification or interchange of one or more components of the binding during manufacturing, by a consumer or dealer to customize the fit, function and/or aesthetics of the binding.