doberman door and window defender w/ chime patio entry security alarm

this is a used alarm that works fine and it is loud......you will need to find a way to stick to the door or other surface......easy fix..plenty of double sided stickers around.........batteries may or may not need replacing.........the smaller piece is a magnet of some form.....when you break the connection the alarm go's off......no manual available but may be online...but no need for 1..........just stick and go......test before to find best place for the magnet...there is a little arrow on the unit and it probably belongs next to it.....tested working unit............near perfect cosmetic condition.... main unit has some specks of markings on the front lower 1/2 and a couple indentation on the back....magnet has a small rub mark on 1 side.....all the glue residue was removed with alcohol.........the magnet still has the sticky pad on it but no stick.....