a float or floats for use with a marine dock structure in which a body in the form of a hollow rectangular block formed of resinous plastic material is provided with a bottom slot in which a board or other mechanism is inserted to space the float bottom wall from the supporting surface when the floats or dock structures in which the floats are a part of are dragged or otherwise moved across the ground to facilitate repair or storage and in which fasteners are provided for attaching the floats to such dock structure .