 First, see the installation manual for recommended mounting locations. Hold the glass break unit upside down and twist the base counterclockwise to separate the base from the detector. Once opened, install the provided batteries into the glass break unit. Once you have determined where to mount the glass break detector, drill three pilot holes using the mounting plate as a guide. Secure the mounting plate with the side with the post near the center, facing away from the mounting surface. Use the provided screws to install the mounting plate. To mount the glass break unit into the mounting plate, find the raised alignment notch on the outside of the mounting plate and the alignment mark on the glass break unit. Align the two marks together and then twist the glass break clockwise to lock it into place. Make sure the rely panel is in programming mode and then press the test button on the top of the unit for up to six seconds. The rely panel... Make sure to subscribe to our YouTube page and click the Show More tab underneath the video where you can view valuable links pertaining to this product, similar how-to videos, and our low-cost, no-contract alarm monitoring services.