High quality closed cell neoprene for maximum longevity. Only black Lycra coating guarantees maximum comfort as well as maximum durability. The adjustment elements are provided with markings to be able to set and replicate your individual foot size in a flash.Comes with 4 screws (M7 x 28mm), 2 plastic top washers and 2 anti-twist plastic bottom inserts to fit with any kind of board specific attachment:Boards equipped with single-screw plugs: just use 2 of the 4 screwsBoards equipped with double-screw plugs: remove the anti-twist plastic bottom inserts and use all 4 screws