A Bridge port opens up the intake port on the leading edge right out to the corner seal track and the continues onto the other side of the track. The steel left between these inner and outer ports serves as a supporting 'bridge' for the corner seals to ride across and gives the name 'bridge' porting.
Bridge ports can be varied in size depending on the engine, for example the 13b RENESIS engine cannot typically be wildly bridge-ported without cause other complications and in some instances the rotor itself can be slightly notched to help increase the area of the port and improve airflow. If all sides of the intake port are bridged, this is known as a full-bridge, as most often utilised on our RX7 13b REW bridge ports. If only the secondary ports are bridged (four-port engines), this is known as a half-bridge whilst if only the auxiliary ports are bridged (six-port engines), this is referred to as an auxiliary port.