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The Type-C connectors connect to both hosts and devices, replacing various Type-B and Type-A connectors and cables with a standard meant to be future-proof. The 24-pin double-sided connector is similar in size to the micro-B connector, with a Type-C port measuring 8.4 millimetres (0.33 in) by 2.6 millimetres (0.10 in). The connector provides four power/ground pairs, two differential pairs for non-SuperSpeed data (though only one pair is populated in a Type-C cable), four pairs for high-speed data bus, two "sideband use" pins, and two configuration pins for cable orientation detection, dedicated biphase mark code (BMC) configuration data channel, and VCONN +5 V power for active cables. Connecting an older device to a host with a Type-C receptacle requires a cable or adapter with a Type-A or Type-B plug or receptacle on one end and a Type-C plug on the other end. Legacy adapters with a Type-C receptacle are "not defined or allowed" by the specification, due to their being able to create "many invalid and potentially unsafe" cable combinations.

Full-featured Type-C cables are active, electronically marked cables that contain a chip with an ID function based on the configuration channel and vendor-defined messages (VDMs) from the USB Power Delivery 2.0 specification. Type-C devices may optionally support bus power currents of 1.5 A and 3.0 A (at 5 V) in addition to baseline bus power provision; power sources can either advertise increased USB current through the configuration channel, or they can support the full power delivery specification using both BMC-coded configuration line and legacy BFSK-coded VBUS line.

Alternate modes dedicate some of the physical wires in the Type-C cable for direct device-to-host transmission of alternate data protocols. The four high-speed lanes, two sideband pins, and (for dock, detachable device and permanent cable applications only) two non-SuperSpeed data pins and one configuration pin can be used for alternate mode transmission. The modes are configured using VDMs through the configuration channel.