Normally closed magnetic contacts with a short 3/4" switch.
82-4750 - 12V 5.0Ah Rechargable Sealed Lead Acid Battery
ELK Sealed Lead Acid Batteries are excellent for the following applications with regard to size, Amp hour rating, and proper terminal connections: battery backup (for Access Control Systems, Fire Alarm Systems, and Security Alarm Systems), emergency lights, lighte...
26-2003 - Magnetic Alarm Reed Switch - 200V SPST-NO
Magnetic Alarm Reed Switch
3/8” (9mm) Diameter
Operate Gap 3/4” (19mm) min.
18” Wire Leads
Easy and Quick Installation
82-13881 - Recessed Alarm Switch White Stubby Switch And Magnet
82-3362 - 50R Series Switch - w/Neodymium Magnet
50R and 50RF series switches are 1/4" diameter switches designed for applications where a small diameter recessed switch is required. These are ideal for residential applications where no sign of an alarm system should be seen.
I have used MCM for many years and would give high recommendation for getting the job done right.