Abstract: A seat construction for a boat comprises a support sleeve arranged for mounting on the boat with a longitudinal axis vertically of the boat. A seat support element is slidable longitudinally of the sleeve and is confined by an upper bearing element of the sleeve and a lower bearing element of the sleeve. A spring extends between the underside of a boss on the longitudinal pin forming the seat support member and an upper face of the lower bearing element so that the spring is confined within the sleeve member and has a relatively long extent of travel to provide effective flexibility of the seat to accommodate vertical shock.

Abstract: A plurality of sections are fitted together so that they fit around an uninflated tire and they are fastened together to form a rigid cylinder. The tire is then inflated thus holding the now solid rim or track in position. Each section includes a curved base and a ground-surface engaging projection extending therefrom. The curved base includes a planar plate portion at one end and a trailing jaw portion at the other end. The plate portion of one section engages the jaw portion of the next adjacent section and the jaws are then closed over the plate and a fastener such as a rivet or the like, is placed through the jaws and through the plate thus forming the rigid connection. There is room provided in the engagement of the plate with the jaws to adjust the sections before fastening same so that the desired diameter of the finished rim or track may be obtained.