La Marzocco 7/9 mm Conical Group Head Gasket
This gasket fits La Marzocco GS-2, GS-3, Linea, FB-70, GB-5 and FB-80. The thickest version with a bevel, used on older machines with extensive wear on the groups and portafilters. The "7" refers to the thickness on the outside diameter, the flat portion, and "9" refers to the thickness on the inside diameter, up to the peak of the cone shape. Installed correctly, with the cone sloped side facing down, the beveled edge of the cone shape adds an additional surface for a portafilter basket to seal against. La Marzocco old part #L105/B9, new part #H.3.002.