The transmitter and receiver are both labeled, so you can tell which one goes where. Just plug the transmitter into the HDMI port of a player (laptop, desktop, blu-ray player, gaming console, etc) and plug the receiver into a display (monitor, TV, projector, etc).
Coolpie Wireless HDMI Transmitter and Receiver are easy to use, compact, and ideal for projectors placed in hard to reach locations, which make life easier since I don't have to run an HDMI cable along wall and ceiling to your projector.