Intermediate Table and Laravel Relations 5.4

Hello friends, I'm working on an api rest in laravel 5.4 and so far I need to make a relationship between two tables, creating an intermediate one. I'm just not sure if I'm doing it right and I wanted your opinion and advice: for example table roles:

class CreateRolesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('roles', function (Blueprint $table) {
            $table->increments('id');
            $table->string('denominacion');
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('roles');
    }
}

table modules:

class CreateModulesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('modules', function (Blueprint $table) {
            $table->increments('id');
            $table->string('denominacion');
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('modules');
    }
}

and the intermediate table:

class CreateRolesModulesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('roles_modules', function (Blueprint $table) {
            $table->increments('id');
            $table->integer('roles_id')->index();
            $table->integer('modules_id')->index();
            // $table->timestamps();
            });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('roles_modules');
    }
}

and the relationship in the models, role model: use Illuminate \ Database \ Eloquent \ Model; use App \ modules;

class roles extends Model
{
    public function moduls()
    {
        return $this->belongsToMany('modules');
    }

}

Model module:

use Illuminate\Database\Eloquent\Model;

    use App\roles;

    class modules extends Model
    {
        //
        public function rols(){
            return $this->belongToMany('roles');
        }
}

Please tell me, that's fine or how I should do it