A quick heads-up - until the end of the day Audio Pro are offering outlet prices of 50% off, with free shipping. Their 'Add On C3' is a cracking Boom replacement (battery powered too), and the outlet price of GBP125 is a great deal.
https://outlet.audiopro.com/
At the time of writing they have a few left, but they are selling fast.
https://outlet.audiopro.com/
At the time of writing they have a few left, but they are selling fast.