We no longer manufacture replacement parts for model numbers AE-21 and AE-21A. If what you need to replace are the flat beater, wire whip, or dough hook, then the counterparts for the models AE-20 and AE-20A will be compatible with your machine. Please note however, that there will be a small gap between the bottom of the bowl and the accessory when it is attached.  The gap is about 1 inch. You can adjust the height of the bowl to accommodate the difference in height. 

If parts other than the beater, wire whip, and dough hook are needed, please contact us to inquire as there is limited availability of parts for the model numbers AE-21 and AE-21A.