Philips Series 800 (AC0820/30) Air Purifier - White - Used - No Filter. Great automatic air filter/purifier. Certainly powers through the air when turns on or it detects something, but soon settles. A slightly sad story here, this was bought for my Dad as he had lung cancer, and it really helped him breathe more easily. Sadly this is now no longer required and needs to go as it's a bit of a reminder for us. We've had it for just over 18 months but was only in use for around half that. Naturally we've thrown away the original included filter as they should be replaced yearly, but you can pick them up easily for under £30. There is a slight black mark at the bottom on one side of the unit (see picture 3).