# Locked columns

Locked (frozen or sticky) columns are the columns that are visible at all times while the user scrolls the TreeList horizontally.

In order for the locked columns to work properly, configure the following options:

* (Required) Set [`width`](https://www.telerik.com/kendo-react-ui/components/treelist/api/treelistcolumnprops#width) of each column.
* (Required) Set [`locked`](https://www.telerik.com/kendo-react-ui/components/treelist/api/treelistcolumnprops#locked) property of the column.
* (Required) Set `overflow: auto` and `width` in pixels through the [`style`](https://www.telerik.com/kendo-react-ui/components/treelist/api/treelistprops#style) property of the TreeList.

> By default, the columns of the TreeList are not locked.

The following example demonstrates how to lock the `Name` and `Full Time` columns so they remain visible while the user scrolls the TreeList horizontally.

[Demo Source](https://demos.telerik.com/kendo-react-ui/treelist/locked/func/source.txt)

## Suggested Links

* [API Reference of the TreeList](https://www.telerik.com/kendo-react-ui/components/treelist/api/treelistprops)
* [API Index of the TreeList](https://www.telerik.com/kendo-react-ui/components/treelist/api)