This is the same as the F_59, but is made with a softer rubber. 73 x 57 x 8mm. Also available in 8.5 and 9mm versions.
If your portafilters are worn, they may be engaging too far to the right (and if you don't want to buy new portafilters), you may want to consider purchasing one of the thicker gaskets
 "(W_556A) 8mm Soft E-61 Group Head Gasket")
