Is there something I can buy to allow my iphone 5 to work with an iphone 4 player?

I just got a new stereo, but where you can charge your phone and play music from your phone, it's for an iphone 4. I have an iphone 5. Is there like a little thing I can buy so it plugs into the place on the radio, but has like a converter thing so I can plug in my 5 on top of that?

The 30-pin to 8-pin lightning adapter should work. I've even seen generic ones on ebay that work pretty good.