---
title: kIOMaximumBlockCountWriteKey
framework: IOKit
role: symbol
role_heading: Global Variable
platforms: [iOS 16.0+, iPadOS 16.0+, Mac Catalyst 13.0+, macOS 10.1+, visionOS 1.0+]
path: iokit/kiomaximumblockcountwritekey
---

# kIOMaximumBlockCountWriteKey

## Declaration

```swift
var kIOMaximumBlockCountWriteKey: String { get }
```