[kharakterizuyushcha] [s] : - by trapeziform form; By the presence of the framework on the outline of revetment; - presence of central longitudinal edge; - by arrangement on to center the revetments of the bed of [dl] of trade mark; [otlichayushcha] [s] : - by the presence of three cross ribs; - by the fulfillment of the bed of [dl] of the trade mark of the oval form of [prot] by [zhennostyu] down entire width of longitudinal edge and with the edging on the edge; - by the execution of the lateral sides of the framework of revetment with the smooth expansion to the upper side.