RB2-BZ105...CONTACT BLOCK SWITCHES,NORMALLY OPEN+NORMALLY CLOSED,STANDARD TYPE WITH COLLAR
Reed Switch normally open or normally closed | MySensors Forum
2 Position Normally Open + Normally Closed key operated Rotary Switch - Metal bezel - Buy Online - EC Products UK
5Sets Magnetic Reed Switch Normally Open Closed NC NO Door Alarm Window Security/Magnetic Door Switch/Magnetic Contact Switch/Reed Switch (5pcs White) : Amazon.ca: Industrial & Scientific