(under subclass 100) Apparatus including means integral or made separately to present a sealed outer surface both when in a horizontal position or when in a curved position, thereby preventing the undesirable ingress of foreign matter between the tread segments. [figure] [caption]A - Chain track; B - Sprocket wheel; C - Sprockets; D, E - Chain plate; F - Cleat having same thickness as chain plate; G - Opening filled with elastomeric material ; H - Projecting pieces for improved traction
