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# How to Use "Upsell product"? Link Stock and Price of Shopify Variant to Option Value

1. [OPTIS Product Options, Variant](/product-options)
2. [Advanced Setup](/product-options/advanced-setup)

# How to Use "Upsell product"? Link Stock and Price of Shopify Variant to Option Value

Our app supports **product option inventory management**, allowing specific options to be **grayed out when out of stock** and ensuring that inventory updates automatically when a customer purchases an option.

This feature, called **"Upsell product"** links an option to a specific Shopify variant, syncing stock and price automatically. This feature is available in our **$19.99/month plan**:

![](https://storage.crisp.chat/users/helpdesk/website/-/5/3/3/d/533da49442cdb000/2546e99e-6133-4853-8d8e-c37f21_s6ll78.png)

## Step-by-Step Guide to Set Up "Upsell product"
### Step 1: Create Draft Products with Variants

1. In your Shopify store, create a draft product with different variants.
2. Assign stock levels and prices to each variant.

* Example:
* **Black variant:** Stock = **5**, Price = **$0** (only tracks stock).
* **White variant:** Stock = **0**, Price = **$1000** (tracks both stock and price).

![](https://storage.crisp.chat/users/helpdesk/website/-/5/a/5/3/5a533758a0a58800/4cfd1c93-7c25-4479-9225-ce5cc8_6iuvfh.png)

### Step 2: Assign Variants to Product Options

1. In the option set editor, open the option and set **Add-on** to **Upsell product**. Use the **Add-on** column of the **Option values** table (click **Columns** to show it), or **Add-on** in **Option settings** for single-value options.
2. Click the variant field (**Search product**) and, in the **Select product variant** window, select the corresponding Shopify variant for each option value. The window shows each variant's SKU and available quantity (or **Not tracked**).

![](https://storage.crisp.chat/users/helpdesk/website/-/9/0/d/e/90dec03ba927c800/bc06631e-5a26-477c-a979-e96c1b_1azli75.png)

### Step 3: View the Result on Your Storefront

* If a variant is out of stock, the assigned option will be **grayed out** automatically.
* If a variant has stock (for example 4 stocks), then the option linked with this variant will also have 4 stocks

![](https://storage.crisp.chat/users/helpdesk/website/-/9/a/0/7/9a07dec0fed32800/8773b498-9e66-43b2-af7a-2aa520_3qfm4g.png)

* When a customer purchases an option, the inventory updates in real-time (e.g., black stock reduces from 5 to 4).

![](https://storage.crisp.chat/users/helpdesk/website/-/4/d/f/4/4df47f94c4d8f400/7aa19871-e6b7-41a0-9754-4bbd33_15dg6fi.png)

#### Optional: Keep Variants in Draft Mode

* If you do not want these variants to appear as active products in your store, you can keep them in **draft mode** in Shopify.

By following these steps, you can **prevent customers from selecting out-of-stock options** while keeping your inventory automatically updated!