You might want to get one of these if you broke your roast chamber or if you think that it's inevitable that a spare one will come in handy. This chamber works with the SR800 roaster only - not the older Fresh Roast +8 models, SR300, SR500, or SR700 roasters. For +8 contact Home Roasting Supplies directly. You can purchase chambers for the early SR models here.
This roast chamber can be used to boost the batch size of your SR540 - that said, in our experience, the heavier duty fan in the SR800 base unit is necessary to for a successful 8 oz batch.