Make sure the blender blade takes cups with 4 Tabs and 3" Diameter. These cups fit: BL660 (1100 watt), BL663 (1100 watt), BL740, BL770 BL771 BL772 (1500 watt), BL780 (1200 watt), BL810 BL820 BL830. The model number is located underneath the base of the blender and must start with BL. Please make sure that the cups you are replacing and the have "4 TABS". BPA Free.