<local:ProductsCollection 
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:local="clr-namespace:DataGridSamples">
    <local:Product/>
    <local:Product/>
    <local:Product/>
    <local:Product/>
    <local:Product/>
    <local:Product/>
    <local:Product/>
    <local:Product/>
    <local:Product/>
    <local:Product/>
</local:ProductsCollection>