9-pin FireWire 800 was introduced commercially by Apple Inc. in 2003. This newer specification (1394b) and corresponding products allow a transfer rate of 786.432 Mbit/s. It is backwards compatibility to the slower rates and 6-pin connectors of FireWire 400. However, while the IEEE 1394a and IEEE 1394b standards are compatible, connectors are different, making the cables used by previous versions incompatible.