| gridModel | org.apache.tapestry5.grid.GridModel |   | componentResources.container | prop | 
| The object that provides access to bean and data models, which is typically the enclosing Grid component. | 
| index | int |   |   | prop | 
| Optional output parameter that stores the current column index. | 
| lean | boolean |   |   | prop | 
| If true, then the CSS class on each <TH> element will be omitted, which can reduce the amount of output
 from the component overall by a considerable amount. Leave this as false, the default, when you are leveraging
 the CSS to customize the look and feel of particular columns. | 
| overrides | org.apache.tapestry5.PropertyOverrides |   | this | prop | 
| Where to look for informal parameter Blocks used to override column headers.  The default is to look for such
 overrides in the GridColumns component itself, but this is usually overridden. | 
| zone | String |   |   | prop | 
| If not null, then each link is output as a link to update the specified zone. |