This is a Mini Display Port Thunderbolt to DVI VGA HDMI Adapter. With three output ports, you can choose one of them to use at a time, and the functions of the port are as follows
- DVI output, connect the DVI devices using a DVI cable
- HDMI output, connect the HDMI devices using an HDMI cable
- VGA output, connect the VGA devices using a VGA cable
Thanks for looking