The USB Promoter Group announced today that it has finalized the design of the USB Type-C plug , a new type of USB plug that's designed to completely replace every size of all current USB connectors. Like Apple's Lightning cables, the new connector is reversible so that it can be used in any orientation.

According to the USB-IF's press release (PDF), the new connector is "similar in size" to current micro USB 2.0 Type-B connectors (the ones you use for most non-Apple phones and tablets). It is designed to be "robust enough for laptops and tablets" and "slim enough for mobile phones." The openings for the connector measure roughly 8.4mm by 2.6mm.

As we've reported previously, cables and adapters for connecting Type-C devices into older Type-A and Type-B ports will be readily available—the prevalence of these older ports will make any industry-wide shift to USB Type-C an arduous, years-long process.

The new Type-C plug will be compatible with USB 3.1, a revised version of the spec that boosts theoretical transfer speeds from the 5Gbps of USB 3.0 to 10Gbps and that supports delivery of up to 100W of power using the USB Power Delivery spec. First-generation Thunderbolt controllers from Intel have offered 10Gbps of bandwidth for a while now and second-generation controllers double this to 20Gbps, but USB has the advantage of being a much more widely used standard that is generally built into all chipsets and SoCs. The USB 3.1 spec was finalized a year ago, but as of this writing it has yet to show up in any shipping devices.

Finally, the USB Type-C connector has been designed to scale with the USB spec as it gets faster, so as we move beyond USB 3.1 it should be possible to make future cables physically compatible with one another, avoiding ugly solutions like the micro USB 3.0 Type-B connector.