Fake bombs

I'm one of twenty women on the props committee for Josh's school play.  It's a police dramedy.  They need tables, chairs, coffee pot, cups, typewriters, and bombs--fake, of course.  All the easy stuff gets brought in the first day, and of course, after weeks the bombs are still needed.  I ask the director what exactly she envisions.  She says one "mound of dynamite with an old fashioned clock with a ticker".  Then after I create the mound and start my search for the perfect clock, I realize it wasn't so easy.  Clocks don't tick anymore.  People are discarding digital clocks, not analog ones.  Finding ones with arms is a real trick.  Three Goodwill store trips later, I ask her again if it has to tick, she tells me, no, that they can use special effects.  The next day I loving hand her my babies, beaming with pride.  And she smiles and says,  "Um, we really do need an old fashioned kind of clock that will tick."  So we head off to the mall last night and hit a different Goodwill store.  And discover the perfect clock--or so I thought.  What do you think this was?