La Cimbali Flat Group Head Portafilter Gasket
Better than the Bezzera gasket which in my case never took long to leak. This fits perfectly - presumably also the BZ-07 - and lasts for ages with no problems.
Very good gasket, which works better on my BZ 10 than the Bezzera gasket, which leaked far sooner. This one fits perfectly, and lasts for ages.
I have an older Pasquini Livia 90 purchased new in 2004. It came with the square-section gasket that is apparently no longer offered by Pasquini (Pasquini part No, 90907, originally used for the flat gasket is now used for the beveled one). I've been using the beveled one bevel side up so that the cup engages the flat side. This works pretty well, but I have a feeling that the bevel allows the gasket to compress more than it should, and the portafilter handle moves all the way to the right. This flat gasket returns the older Livia 90 to it's original specification.