---
title: "StandardUSB::kDescriptorSizeUSB20ExtensionCapability"
framework: Kernel
role: symbol
role_heading: Enumeration Case
platforms: [macOS 12.0+]
path: kernel/standardusb_tdescriptorsize/standardusb_kdescriptorsizeusb20extensioncapability
---

# StandardUSB::kDescriptorSizeUSB20ExtensionCapability

## Declaration

```occ
StandardUSB::kDescriptorSizeUSB20ExtensionCapability = kIOUSBDescriptorSizeUSB20ExtensionCapability
```