**Data Modeling Hub > Events > Add event**.
3. In the **Name** field, enter `product.backInStock`.
In the API and SDK, the name parameter is usually called `action` or `action name`.
4. Optionally, define a human-friendly display name that will be shown in the **Data Modeling Hub** and **Decision Hub**.
5. Optionally, in the **Description** field, enter the description of the event.
6. Enable the **Make this event available to anonymous profiles without JWT** toggle.
7. Click **Apply**.
8. In the list of events, find the event you just created.
9. On the right side of the screen, click **Add property**.
10. In the **Source parameter** field, enter `sku`.
11. In the **Property name** field, enter a human-readable label for display in the Synerise platform.
12. Optionally, in the **Description** field, you can add an explanation about the purpose of this parameter.
13. To complete the process, click **Save**.
## Create an aggregate with products for which the customer has signed up for notifications
---
The aggregate created will later be used in workflow to check which products have returned to stock.
> **Behavioral Data Hub > Live Aggregates > Create aggregate**.
2. As the aggregate type, select **Profile**.
2. Enter the name of the aggregate.
3. Click **Analyze profiles by** and select **Last multi** and in the **Size** field, enter `100`.
5. From the **Choose event** dropdown list, select the **form.submit** event.
6. As the event parameter, select **sku**.
7. Click **+ where** button.
8. From the **Choose parameter** dropdown list, select the **form type** parameter.
9. From the **Choose operator** dropdown list, select **Equal**.
10. Enter the name of the form. In our case it's `back in stock alert`.
11. Set the period from which the aggregate will analyze the results to the last **30 days**.
12. Save the aggregate.
**Behavioral Data Hub > Live Aggregates > Create aggregate**.
2. As the aggregate type, select **Profile**.
2. Enter the name of the aggregate.
3. Click **Analyze profiles by** and select **Last multi** and in the **Size** field, enter `100`.
5. From the **Choose event** dropdown list, select the **product.backInStock** event.
6. As the event parameter, select **sku**.
7. Set the period from which the aggregate will analyze results to the last **30 days**.
8. Save the aggregate.
{
"sku":"
{% set signedProducts = [] %}
{% set receivedProducts = [] %}
{% set finalSku = [] %}
{% aggregate LAST-SKU-SIGNED %} {# aggregate collecting product sku #}
{% for sku in aggregate_result|reverse %} {# saving sku from aggregate to signedProducts variable #}
{% do signedProducts.append(sku) %}
{% endfor %}
{% endaggregate %}
{% aggregate LAST-SKU-RECEIVED %} {# aggregate collecting product sku sended to user #}
{% for sku in aggregate_result|reverse %} {# saving sku from aggregate to receivedProducts variable #}
{% do receivedProducts.append(sku) %}
{% endfor %}
{% endaggregate %}
{% for sku in signedProducts %}
{% catalogvar.catalog(sku).availability %}
{% if catalog_result == 'in stock' %} {# condition to check if products are availability#}
{% if sku in receivedProducts|join(',') %} {# condition that adds a comma to items #}
{% else %}
{% do finalSku.append(sku) %}
{% endif%}
{% endif %}
{% endcatalogvar %}
{% endfor %}
{% set counter = 0 %}
{% for sku in finalSku %} {# listing the final sku in the sku parameter #}
{% set counter = counter + 1 %}
{{sku}}
{% if counter < finalSku|length%},{% endif %}{%endfor%}"
}
{% set sku_array = event.params.sku %} {% set sku_from_array = sku_array|split(',') %} <ul> {% for sku in sku_from_array %} <li data-snr-ai-product-id="{% catalog.Snrs-produktu-ogTag(sku).product:retailer_part_no %}"> <a class="snrs-AI--item-link" href="{% catalog.Snrs-produktu-ogTag(sku).og:url %}" title="{% catalog.Snrs-produktu-ogTag(sku).og:title %}"> <img src="{% catalog.Snrs-produktu-ogTag(sku).og:image %}" class="products-slider__item-image snrAI-product-image snrAI-product-image-{% catalog.Snrs-produktu-ogTag(sku).og:image %}" width="90" alt="{% catalog.Snrs-produktu-ogTag(sku).og:title %}" id="snrAI-image-{% catalog.Snrs-produktu-ogTag(sku).product:retailer_part_no %}"> <h3 class="snrs-AI-product--product-name"> <span class="snrs-AI-product--name-first">{% catalog.Snrs-produktu-ogTag(sku).og:title %}</span> </h3> </a> </li> {% endfor %} </ul>