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# IOUSBDescriptorHeader

The base descriptor header.

```
struct IOUSBDescriptorHeader;
```

## Overview

For more information about descriptors, see section 9.5 of the USB 2.0 specification at <https://www.usb.org/>.

## Topics

### Getting the Descriptor Properties

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

The number of bytes in the descriptor.

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

The type of the descriptor.


---

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