Package Includes  2 sets - Magnetic door switch Normally opened 
Please read before buying! 
Package includes  1 set of N/O magnetic switch 
Please read before buying!  There is a common misunderstanding with n/o and n/c. It comes from the home security industry just making up there own standards and not understanding the universal switch meanings.  n/o means normally open or if you have a magnet touching the led or motor would be on.  N/C means Normally closed or if you have a magnet touching the motor or led would be OFF.   in other words you wire this switch up to a door when the door is closed and the magnet is touching the alarm system would be on. and when you open the door the alarm system would be off if you have any questions please email me before buying.