Subscribe to Make Magazine Today!


Instructables editor Randy Sarafan created this amazingly useful tutorial that discreetly checks that your fly isn’t down and alerts when it is!

Basically, this is a device that lets you discreetly check in public whether or not your pants fly is up. By pressing a button located in the watch pocket of your pants, a small pager motor alerts you to whether or not the zipper is up. Basically, the zipper of the pants was enhanced with two strands of conductive thread which form a complete circuit when bridged. A small circuit board with a battery, button and motor attached then snaps into the watch pocket. Finally, when the button is pressed, and the zipper is closed, the circuit is completed and the motor vibrates.


Andrew Salomone

Andrew Salomone

Artist, writer, and teacher who makes work about popular culture, technology, and traditional craft processes.

  • dislexas

    I just pinch the side of my pant (like touching my hip). You can feel the different tensions between the buttoned end and the unzipped zip.

  • David

    A woman friend said my fly was open.
    I replied:
    “Men only know what women tell them. Women tell men that men should look at a woman in the eye and not at her chest. Why are you looking at my crotch instead of looking me in the eye?”
    Stopped her cold and left her speechless. Even her women friends laughed.

    • David

      Small group of good friends with a good sense of humor as well as political awareness in a private setting. .

    • Fritoeata

      Well said! I would do the same thing (given my relationship with the woman)!

  • Lensdigital

    Make it post to twitter! #flyopen

  • kurtroedeger

    Great, so now I’m out in public with my fly down and my pants vibrating.

  • Fritoeata

    So… which Make staff member is this in the first pic?

  • evilution

    why not just create a loop out of string or an old lace that passes through the hole in the zip tab, loop this around the button before you button up your trousers. That way they zipper can’t come down so you don’t need to keep checking.