---
title: bLength
framework: usbdriverkit
role: symbol
role_heading: Instance Property
path: usbdriverkit/iousbbosdescriptor/blength
---

# bLength

The size of the descriptor in bytes.

## Declaration

```occ
uint8_t bLength;
```

## See Also

### Accessing the Descriptor Properties

- [bDescriptorType](usbdriverkit/iousbbosdescriptor/bdescriptortype.md)
- [wTotalLength](usbdriverkit/iousbbosdescriptor/wtotallength.md)
- [bNumDeviceCaps](usbdriverkit/iousbbosdescriptor/bnumdevicecaps.md)