?? This 2 pack FireWire 400 to 800 adapter allows you to connect your old FireWire 400 cable to FireWire 800 port equipped host devices?? IEEE-1394 Type A Female (6 pin) to IEEE-1394 Type B Male (9 pin), plug n play and hot swappable?? Makes your FireWire 400 peripherals work again, such as digital camera, hard drive, audio interface, DVD etc. ?? Compatible with Mac Pro, MacBook Pro, Mac Mini, iMac and those host devices with FireWire 800 port. If your host device has only tb port, then you will need another adapter in addition: tb to FireWire 800 (Not supplied) ?? Stable and high speed transmission, data transfer rate up to 400Mbps