---
title: "GridTrackSpec"
description: "Marker interface to enable vararg usage with [GridTrackSize].

This allows the configuration DSL to accept [GridTrackSize] items in a vararg (e.g.,
`columns(Fixed(10.dp), Flex(1.fr))`), bypassing the Kotlin limitation on value class varargs."
type: "interface"
---

<div class='type'>Interface</div>


<a id='references'></a>

<div class='sourceset sourceset-common'>Common</div>



```kotlin
@ExperimentalGridApi sealed interface GridTrackSpec
```


Marker interface to enable vararg usage with `GridTrackSize`.

This allows the configuration DSL to accept `GridTrackSize` items in a vararg (e.g.,
`columns(Fixed(10.dp), Flex(1.fr))`), bypassing the Kotlin limitation on value class varargs.