5 x Electrotec CO03 Burglar Alarm White Surface Door Contacts - Professional Quality, 5 Terminal Magnetic Reed Switch Type.

I bought these for a garage door monitoring project I've been building. I am using two on each door, so I can tell via the little electronic box of tricks I've come up with (based around an ESP8266 and some 5V relays) if a door is fully open, fully closed, or somewhere in between. They seem to be good quality switches, and trigger when the magnet is within about 1-2cm, they don't need to be virtually touching.

this type of switch system I have used before and in my opinion is still very reliable and good value when they last about 30+ years of service .

Easy to fit. My alarm system fitted over twenty years ago, so a couple of existing magnetic contacts were causing false activations. Have fitted two of a pack of five so far, and have cured the problem. Would buy again if necessary.

Used 3 pairs of contacts for new doors, super glued them to the new composite doors and frames they are better quality than previously ordered

Some didn't work but other fitted easily

Worked perfectly very happy with item (only used the reed swich part not the intrusion detection pins)

Extremely good value for money and they all worked = Good Product

Standard surface door contacts (when both parts are together contact is closed). Excellent product for the money complete with screws.