Hello pvl and thank you for your question.
The GE Wireless Door and Window Alarm Kit does not have a controller. Each item acts independently. You can purchase additional door and window alarms as needed since they are independent of each other.
Installation instructions can be downloaded at:http://www.jascoproducts.com/suppor...
(Search on 51107 GE Wireless Alarm System Kit English - Spanish Manual)
Best wishes with your project.