master/app/models/Brends.php

<?php

namespace app\models;
use app\models\ProductsBrends;

class Brends extends \yii\db\ActiveRecord
{
    public static function tableName()
    {
        return 'catalog_brends';
    }
        public function getProductsBrends()
        {
            return $this->hasMany(ProductsBrends::className(), ['brend_id' => 'id']);
        }     
}