Stainless steel light box has a heavy duty design to fit 4 inch round lights. Single measures 6″ x 6″ x 3″ LB663ST-1, double measures 6″ x 12″ x 3″ LB663ST-2, triple measures 6″ x 18″ x 3″ LB663ST-3. (Diamond tread items pictured, stainless photo not available)