Replacement Bottom Base Ring Plastic Cap Compatible with Commercial Hamilton Beach Blenders such as HB908, HB909, 908, 909, 919 This base is compatible with hamilton beach commercial blades that the outside diameter of the gasket or the base of the blade is 2 5/8" (A little less than 2.75") Color: Black Replacement Bottom Base Ring Plastic Cap, Compatible with Commercial Hamilton Beach Blenders such as HB908, HB909, 908, 909, 919. This item replaces part number 990035900, 3121-207-1300.