Absolutely brilliant. So pleased. My clk had been parked on my mums drive for months and wouldn’t start. Because the doors locks worked , but the ignition didn’t , I thought I neeeded a new electronic ignition barrel , which would have cost hundreds of pounds from Mercedes. Fortunately it turned out to be the key broken inside. I found the master locksmith online as an obvious choice ( reading reviews) to fix it, I posted it off and just a couple of days later it was returned with a brand new casing, even new batteries for £35. And now my car works again, thank you, can’t begin to say how relived I am. Will be using again for another broken key soon ...