# Price comparison

For **Roundups** and **Reviews**, you can enable the price comparison feature to display additional "Buy Now" buttons from alternative product sources.

<figure><img src="https://669767761-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2dXzBR7q3Us45M1tvAnJ%2Fuploads%2FGdU5cZO2uEgi28morLGM%2Fimage.png?alt=media&#x26;token=c0ed2732-bf75-4120-b932-53ceade41af5" alt=""><figcaption></figcaption></figure>

### **How Price Comparison Works**

The most reliable way to merge products from different modules into a single comparison list is by searching **via EAN**.

<figure><img src="https://669767761-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2dXzBR7q3Us45M1tvAnJ%2Fuploads%2FFY0cJ8NwbRrsRYNUvXF8%2Fimage.png?alt=media&#x26;token=795d9096-010c-452a-836a-05467265f528" alt=""><figcaption></figcaption></figure>

{% hint style="warning" %}
To use this feature, you must enable **Content Egg** modules that support **EAN search**, in addition to your **main affiliate module**.
{% endhint %}

#### **Supported Modules for EAN Search**

{% hint style="success" %}
We recommend using [Sovrn](https://tmniche-docs.keywordrush.com/getting-started/quick-start), as it has a large product database and does not require individual advertiser approvals.
{% endhint %}

* Amazon
* Amazon No API
* BestBuy
* Bol.com
* CJ Products
* eBay
* Kelkoo
* Kieskeurig.nl
* Sovrn (VigLink)
* Tradedoubler Products
* Tradetracker Products
* Walmart
* Webgains