jiggler

noun3

1. •
   Someone or something that jiggles.
2. •
   A small, heavy valve on top of a pressure cooker to release steam periodically.
3. •
   (slang) A key, now especially a car key, that has been partially ground down so that it will open many locks.

   • I knew about the whole key “jigglers.” Basically, random car keys are shaved down with a file, rounding out sharp edges. — 2011