Vintage "Phone Magnet"

I've been going through boxes of photos and souvenirs, trying to get rid of things we no longer need.

In one box of mainly photos I came across this Zenith "phone magnet" in its original box...

What was a phone magnet?! Neither Terry nor I had any idea.

Who had it belonged to? My father? Terry's grandmother? 

I looked up Zenith phone magnet online - and discovered that it was neither a phone nor a magnet, but a hearing aid!

To toss? Or to keep as a vintage souvenir?! 

(That's always the hard decision!)