Putting `QuantitativeValue` from schema.org into `td` element

Question

I have following piece of code as part of my Product:

<tr>
   <th>Width:</th>
   <td itemprop="width" href="http://schema.org/QuantitativeValue">
      <?php echo $product->width."mm"; ?>
   </td>
</tr>

Unfortunately it generates following error:

Attribute href not allowed on element td at this point.`

Answer 1

The width property expects an item (Distance or QuantitativeValue) as value.

So you need something like this:

<td itemprop="width" itemscope itemtype="http://schema.org/QuantitativeValue">
</td>