I have a wahl pro series 9551 and the cha...

Hello Lisa, Give the folks at www.electricshaver.com a try, as they have parts for most major brands of electric shavers and clippers in stock. You can also call them at 1-888-476-1785 and provide them with your model number and they can get the correct charger cord for your model.

Here's a link to a page that has a couple of charger cords that might work for your Wahl 9551, but you'll need to verify the voltage on the existing (broken) charger against the ones listed.

It would be best to contact them to make sure you get the right charger for your shaver. I hope you find this Very Helpful and best regards!