Univen Gasket Seal for Stovetop Espresso Coffee Makers 1 Cup fits Bialetti, Imusa, BC, etc. Replacement Gasket Seal for 1 Cup Stovetop Espresso Makers Fits Bialetti and Many Other Brands of 1 Cup Stove Top Espresso Makers Fits Imusa B120-41V 1 cup and BC Classic Bene Casa 17710 1 cup espresso makers Inside diameter 1.5" (39mm), Outside diameter 2" (52mm).