---
title: indexType
framework: metal
role: symbol
role_heading: Instance Property
path: metal/mtl4accelerationstructuretrianglegeometrydescriptor/indextype
---

# indexType

Configures the size of the indices the indexBuffer contains, which is typically either 16 or 32-bits for each index.

## Declaration

```swift
var indexType: MTLIndexType { get set }
```