Before purchasing below three comditons must be met at the same time: 1)Your original blender base and blade are 6 fins. 2)The diameter of your original blade is 3.35 inch/8.5cm. 3)This blade is Only fit for 16oz Cup with 4 TABS. NOTE: Please check your blender model and fins quatity before purchasing. DO NOT BUY this if your blade has 5 or 7 fins Compatibility: Compatible with Ninja BL770AMZ Mega Kitchen System, Ninja BL660 Professional Compact Smoothie & Food Processing Blender, Ninja professional blender BL663, BL663CO, BL665Q, BL771, BL772, BL780, BL740. Not suitable for models with 12oz/18oz/24oz/32oz cups or the 4" 10cm blade. NOT COMOATIBLE WITH Nutri Ninja Blender Auto iQ 900W BL450-70, BL451-70, BL454-70, BL455-70, 1000W BL480-70,BL480W-70, BL481-70, BL482-70, BL483-70,BL484-70. NOT Compatible with Nutri Ninja Blender Auto-iQ: NN100, NN100A, NN101, NN101-30, NN102, NN210, BL450-30, BL454Q, BL480-30, BL481-30, BL482-30, BL483-30,BL485 etc NOT Compatible with NINJA ULTIMA BLENDER: BL810QSL 30 /BL830CB 30 / BL810QON 30 /BL810 30 /BL820 30 /BL830 30. Not for 5 Fins Blade such as these models: QB3000, QB3000SS, QB3001, QB3001SS, QB3004, QB3005 etc.(Please check all pictures carefully for compatibility before purchasing) Compatibility: Compatible with Ninja BL770AMZ Mega Kitchen System, Ninja BL660 Professional Compact Smoothie & Food Processing Blender, Ninja professional blender BL663, BL663CO, BL665Q, BL771, BL772, BL780, BL740.