> ## Documentation Index
> Fetch the complete documentation index at: https://docs.upstackdata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Items Array

> Product details for e-commerce events — id, name, price, quantity, brand, category, and variant properties.

For events involving products, use the `items` array. Required for all product-related events.

## Items Array Structure

```javascript theme={null}
window._upstack('track', 'purchase', {
  transactionId: 'ORD-12345',
  value: 149.99,
  currency: 'USD',
  items: [
    {
      id: 'SKU-001',            // Product ID or SKU
      name: 'Running Shoes',     // Product name
      price: 89.99,             // Unit price
      quantity: 1,              // Quantity (default: 1)
      brand: 'Nike',            // Brand name
      category: 'Footwear',     // Primary category
      variant: 'Blue / Size 10' // Size, color, etc.
    },
    {
      id: 'SKU-002',
      name: 'Athletic Socks',
      price: 14.99,
      quantity: 4,
      brand: 'Nike',
      category: 'Accessories'
    }
  ]
});
```

## Item Properties

| Property       | Type   | Required | Description                                                        |
| -------------- | ------ | -------- | ------------------------------------------------------------------ |
| `id`           | string | No       | Product ID or SKU                                                  |
| `name`         | string | No       | Product name                                                       |
| `price`        | number | No       | Unit price                                                         |
| `quantity`     | number | No       | Quantity (default: 1)                                              |
| `value`        | number | No       | Total value for this item (typically `price × quantity`)           |
| `currency`     | string | No       | Per-item currency override (ISO 4217 code, e.g., `"USD"`)          |
| `brand`        | string | No       | Brand name                                                         |
| `category`     | string | No       | Primary category                                                   |
| `category2`    | string | No       | Secondary category                                                 |
| `category3`    | string | No       | Tertiary category                                                  |
| `category4`    | string | No       | Fourth category level                                              |
| `category5`    | string | No       | Fifth category level                                               |
| `variant`      | string | No       | Size, color, or other variant                                      |
| `sku`          | string | No       | Stock keeping unit                                                 |
| `discount`     | number | No       | Discount amount per item                                           |
| `coupon`       | string | No       | Item-level coupon code                                             |
| `url`          | string | No       | Product page URL                                                   |
| `imageUrl`     | string | No       | Product image URL                                                  |
| `content_type` | string | No       | `"product"` for individual items or `"product_group"` for variants |
| `index`        | number | No       | Zero-based index of item in the items array                        |
| `locationId`   | string | No       | Per-item store or location identifier                              |
| `unitCost`     | number | No       | Cost per unit (for margin calculations)                            |
| `unitMargin`   | number | No       | Margin per unit (for profitability tracking)                       |

<Note>
  If `value` is not provided, it is computed automatically as `price × quantity`.
</Note>

## Items Array by Event

```javascript theme={null}
// View a product
window._upstack('track', 'view_content', {
  items: [{
    id: 'SKU-001',
    name: 'Running Shoes',
    price: 89.99,
    category: 'Footwear'
  }]
});

// Add to cart
window._upstack('track', 'add_to_cart', {
  value: 89.99,
  currency: 'USD',
  items: [{
    id: 'SKU-001',
    name: 'Running Shoes',
    price: 89.99,
    quantity: 1
  }]
});

// Begin checkout
window._upstack('track', 'initiate_checkout', {
  value: 104.98,
  currency: 'USD',
  items: [
    { id: 'SKU-001', name: 'Running Shoes', price: 89.99, quantity: 1 },
    { id: 'SKU-002', name: 'Athletic Socks', price: 14.99, quantity: 1 }
  ]
});
```