Apart from USB4, every USB version supports Type-B connectors, including USB 3.0, USB 2.0, and USB 1.1. The second type of “B” connector, called Powered-B, also exists, but only in USB 3.0. USB 3.0 Type-B connectors are often blue, while USB 2.0 Type-B and USB 1.1 Type-B connectors are often black. That’s not always the case because the manufacturer can choose any color for USB Type-B connectors and cables.
USB Type-B Uses
USB Type-B receptacles are often on larger computer devices like printers and scanners. Sometimes, you’ll find Type-B ports on external storage devices like optical drives, floppy drives, and hard drive enclosures. Type-B plugs are typically at one end of a USB A/B cable. The USB Type-B plug fits into the Type-B receptacle on the printer or another device, while the USB Type-A plug fits into the type A receptacle located on the host device, like a computer.
USB Type-B Compatibility
The Type-B connectors in USB 2.0 and USB 1.1 are identical, meaning that the USB Type-B plug from one USB version will fit into the Type-B receptacle from both its own and the other USB version. USB 3.0 Type-B connectors are a different shape from previous ones, so the plugs do not fit in those receptacles. However, the USB 3.0 Type-B form factor was designed in such a way to allow previous USB Type-B plugs from USB 2.0 and USB 1.1 to fit with USB 3.0 Type-B receptacles. In other words, USB 1.1 and 2.0 Type-B plugs are physically compatible with USB 3.0 Type-B receptacles, but USB 3.0 Type-B plugs are not compatible with USB 1.1 or USB 2.0 Type-B receptacles. USB 3.0 Type-B connectors have nine pins, several more than the four pins found in previous USB Type-B connectors, to allow for a faster USB 3.0 data transfer rate. Those pins had to go somewhere, so the Type-B shape had to be altered somewhat. See our USB Physical Compatibility Chart for a graphical representation of physical compatibility, which should help.
