# Assign values for the product additional custom fields

## Overview

Use this method to assign values to the additional fields for products.

## Use case

1. Add an HTML link or button on your page like the one below.
2. Create a JavaScript click handler to execute the Inline Client desired methods.
3. Set your currency using the theTwoCoInlineCart.cart.setCurrency('USD') method.
4. Use the TwoCoInlineCart.products.add({code, quantity, additionalFields}) method to prepare your products.
5. The **additionalFields** property should contain a list of objects with the code of the field and its value.
6. Use the TwoCoInlineCart.cart.checkout() method to show the cart on your page.

## Sample request

### HTML

```html
<a href="#" class="btn btn-success" id="buy-button">Buy now!</a>
```

### JavaScript

```javascript
window.document.getElementById('buy-button').addEventListener('click', function() {
  TwoCoInlineCart.cart.setCurrency('USD');

  TwoCoInlineCart.products.add({
    code: '2CO3MONTHS',
    quantity: 1,
    additionalFields: [
      // textbox type example
      {
        code     : 'NewsletterPolicy12345768',
        value    : 'Some text value'
      },
      // listbox type example
      {
        code     : 'cart2cotestlist',
        value    : 'YES'
      },
      // hidden type example
      {
        code     : 'HiddenID123',
        value    : 'Some text for the hidden field'
      },
      // checkbox type example
      {
        code     : 'cart2cotest',
        value    : true
      }
    ],
  });

  TwoCoInlineCart.cart.checkout();
});
```

## Demo

After defining the additional fields for your products using the above method, your cart should look like this:

{% embed url="<https://codepen.io/2checkout-documentation/pen/bXLGXw>" %}


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