/**
  * @return \yii\db\ActiveQuery
  */
 public function getRubberItem()
 {
     return $this->hasOne(RubberItems::className(), ['id' => 'rubber_item_id']);
 }
 public function getRubberItems()
 {
     return $this->hasMany(RubberItems::className(), ['id' => 'rubber_item_id'])->viaTable('main_rubber_items', ['main_id' => 'id']);
 }