offer.php

<?php
 
namespace Bitrix\Catalog\Controller\Product;
 
use Bitrix\Catalog\ProductTable;
 
final class Offer extends Base
{
    protected const TYPE = ProductTable::TYPE_OFFER;
 
    protected function getAllowedProductTypes(): array
    {
        return [ProductTable::TYPE_OFFER, ProductTable::TYPE_FREE_OFFER];
    }
}