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# IOUSBDeviceCapabilityUSB2Extension

The structure for the USB 2 extension device capability.

```
struct IOUSBDeviceCapabilityUSB2Extension;
```

## Overview

See USB 3.0 9.6.2.1: USB 2.0 Extension.

## Topics

### Accessing the Descriptor Properties

[`uint8_t bLength;`](/documentation/USBDriverKit/IOUSBDeviceCapabilityUSB2Extension/bLength)

[`uint8_t bDescriptorType;`](/documentation/USBDriverKit/IOUSBDeviceCapabilityUSB2Extension/bDescriptorType)

[`uint8_t bDevCapabilityType;`](/documentation/USBDriverKit/IOUSBDeviceCapabilityUSB2Extension/bDevCapabilityType)

[`uint32_t bmAttributes;`](/documentation/USBDriverKit/IOUSBDeviceCapabilityUSB2Extension/bmAttributes)


---

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