Did you know that when your tyre tread depth reaches just 3mm your wet grip is dramatically reduced?
That's why it's important you check your tyre tread regularly, but perhaps you don't have a centimetre or other measuring tool at hand. Well, open your wallet and get out a 20c coin. All you have to do is place the coin on the small tread depth measuring point (check for the arrow on your tyre to locate it) and check if it reaches the bill of the platypus.
It does? Then there's more than 3mm of tread left on your tyre and you're good to go.
It doesn't? Time for some new rubber to keep you safe on the road.
Remember that most new tyres come with about 8-9mm of tread, so if there's less then 3mm left their grip on the road is minimal, their ability to disperse water reduced and your safety at stake.