before you go and buy any fancy cleaning products try this.
![](./images/smilies/spacer.gif)
give them a gentle scratch with your fingernail.
![](./images/smilies/spacer.gif)
you may well find that the grey discolouration isn't due to faded plastic but is just a build up of general gunk
![](./images/smilies/spacer.gif)
(sweat etc.
![](./images/smilies/spacer.gif)
).
![](./images/smilies/spacer.gif)
You should be able to get them back to shiny black if this is the case!
![](./images/smilies/spacer.gif)
I was told this little trick by someone, thought it was a bit crazy but tried it out and it works!
![](./images/smilies/spacer.gif)
So save your pennies and get scratchin'!