Sorry for the tardy report. It worked quite well for a driveway alert. I had my old homeplace (unoccupied) broken into and several keepsake items stolen, so i put it up there as an alert in the future. I caught the vandals inside the house at 2am, they ran out the back door but left their car and burg tools behind. Police arrested car owner the next day and he confessed. Two months later had some things stolen from freezer in my barn about 100 yard behind my house. I put one in the barn and the next nite they came back,,,,,slipped up on them on foot and lighted the barn up with a spotlight. Ordered them outside but no one came out. I eased up to barn window and saw no one and move slightly past the open door as one came running out the barn door with a gun in his hand, i fired three times at him but apparently missed, chased him towards my house and couldnt fire anymore because of the direction of fire. Police came with helos and dogs etc, no joy on the vandal. You woud not believe the adrenaline that pumps each time that alarm goes off, it sounds each time the motion breaks the beam. They left the gate open at the barn during the first robbery of barn, all my cows were out on the road and that could have been disasterous. The old house was hit again during daylite when i wasnt home and they never saw the unit. I would highly recommend it for driveway or a poor-mans burglar alarm. I have three of the units now, each set on a different tone. Quarter mile might be iffy if you had any obstructions, but the one in the old house as described in my first post worked at over an eighth mile. chuck