# USB 2 Standard-B plug > a legacy USB plug that preceded USB-C (“B” indicating the peripheral device end) **Wikidata**: [Q27688486](https://www.wikidata.org/wiki/Q27688486) **Source**: https://4ort.xyz/entity/usb-2-standard-b-plug ## Summary The USB 2 Standard-B plug is a legacy USB connector located at the peripheral device end of a cable, designed to carry USB 1–2 data signals and power. Officially designated as the USB 2.0 Standard-B plug, it is classed as a legacy connector that preceded the USB-C standard. It connects to receptacles on devices such as printers or scanners and features a specific 4-pin configuration. ## Key Facts - **Official Name:** USB 2.0 Standard-B plug. - **Function:** Serves as the peripheral device end of a cable, distinct from the host (Standard-A) end. - **Succession:** It is a legacy connector that preceded the USB-C plug, by which it was replaced. - **Pinout Configuration:** Features 4 pins: Pin 1 (VBUS, 5V, Red), Pin 2 (D−, White), Pin 3 (D+, Green), and Pin 4 (GND, Black). - **Compatibility:** Designed to connect with USB 2 Standard-B, USB 3 Standard-B, and USB Powered-B receptacles. - **Classification:** It is an instance of the "USB Standard-B plug" and "USB 2 Standard plug" classes. - **Differentiation:** Distinct from the USB 2 Standard-A plug, USB 2 Micro-B plug, USB Mini-B plug, and USB 3 Standard-B plug. - **Aliases:** Also known as the Hi-Speed USB Standard-B plug, USB 1.1 Standard-B plug, and Standard USB 2.0 Type-B plug. ## FAQs ### Q: What is the USB 2 Standard-B plug used for? A: This plug is found on the end of a USB cable that connects to a peripheral device, such as a printer or scanner, rather than the computer. It carries USB 1–2 data and power to the device. ### Q: What are the specific pins and wire colors for this plug? A: The plug uses a 4-pin layout: Pin 1 is VBUS (Red) for power, Pin 2 is D− (White), Pin 3 is D+ (Green) for data, and Pin 4 is GND (Black) for ground. ### Q: Can a USB 2 Standard-B plug fit into a USB 3 Standard-B receptacle? A: Yes, the structured properties indicate that the USB 2 Standard-B plug is designed to connect with USB 3 Standard-B receptacles, ensuring backward compatibility with newer ports. ### Q: Is the USB 2 Standard-B plug still the standard for new devices? A: No, it is considered a legacy connector that has been replaced by the USB-C plug. ## Why It Matters The USB 2 Standard-B plug represents a critical era in the standardization of peripheral connectivity. Before the advent of the reversible USB-C connector, the Standard-B plug was the industry standard for linking "high-speed" (USB 2.0) and full-speed/low-speed (USB 1.x) peripherals to hosts. Its distinct shape—different from the flat Standard-A plug used on computers—enforced a strict directional topology, preventing users from incorrectly connecting two computers directly to each other without a specialized bridge cable. While it is now classified as a legacy connector, its physical design allowed for backward compatibility with the subsequent USB 3.0 Standard-B receptacles. This longevity ensured that millions of printers, scanners, and external drives remained functional even as computer hardware advanced. The plug's transition from USB 1.0 through USB 2.0 "Hi-Speed" established the physical link for the most ubiquitous version of USB in history, making it a foundational component in the history of computing hardware. ## Notable For - **Enforcing USB Topology:** Its design physically differentiated the "peripheral device end" from the "host end" (Standard-A), preventing incorrect network topologies. - **Carrying Hi-Speed Data:** As the "USB 2 Standard-B plug," it specifically enabled the 480 Mbit/s transfer rates defined in the USB 2.0 specification. - **Legacy Precedence:** It is the immediate predecessor to the modern USB-C plug in the timeline of USB connector evolution. - **Receptacle Compatibility:** Uniquely designed to fit not only its native USB 2 receptacle but also the later USB 3 Standard-B and USB Powered-B receptacles. ## Body ### Definition and Classification The **USB 2 Standard-B plug** is a class of legacy USB plugs located at the peripheral device end of cables. It is officially named the **USB 2.0 Standard-B plug**. It falls under the broader classes of "USB Standard-B plug" and "USB 2 Standard plug." It is distinct from the USB 2 Standard-A plug, which connects to the host controller. ### Technical Specifications The connector utilizes a 4-pin interface to transmit power and data. * **Pin 1 (VBUS):** Red wire; provides +5V power supply. * **Pin 2 (D−):** White wire; data negative. * **Pin 3 (D+):** Green wire; data positive. * **Pin 4 (GND):** Black wire; ground signal. ### Evolution and Relationships This plug is categorized as a legacy connector that **preceded USB-C**. It is the opposite counterpart to the **USB 2 Standard-B receptacle** (the port on the device). While it has been **replaced by the USB-C plug** in modern standards, it maintains listed compatibility with: * USB 2 Standard-B receptacle * USB 3 Standard-B receptacle * USB Powered-B receptacle It is differentiated from other mobile and legacy formats such as the USB 2 Micro-B plug, USB Mini-B plug, and the USB 3 Standard-B plug (which has additional pins). ### Nomenclature The plug is known by several aliases reflecting its version history and speed capabilities, including: * Hi-Speed USB Standard-B plug * USB 1.0 / 1.1 / 1 Standard-B plug * Standard USB 2.0 Type-B plug ## References 1. [Source](https://www.usb.org/document-library/usb-31-legacy-cable-and-connector-revision-10) 2. [Source](https://www.usb.org/document-library/universal-serial-bus-31-legacy-connectors-and-cable-assemblies-compliance-document) 3. [Source](https://www.usb.org/document-library/usb-32-revision-11-june-2022) 4. [Source](https://www.usb.org/document-library/usb-type-cr-connectors-and-cable-assemblies-compliance-document-rev-21b) 5. [Source](https://www.usb.org/document-library/usb-type-cr-cable-and-connector-specification-release-24) 6. [Source](https://www.usb.org/document-library/usb-20-specification)