Replace only your Motor Base instead buying a complete and expensive new unit Fits on the following model, BL642W, BL640 BL641 BL642 BL642W BL642W1 BL642Z and Fits all Units that have 7 fins on bottom of blade Original Ninja Motor Base replacement is designed to keep your blender running so you can enjoy your favorite drinks, smoothies or milkshakes. The Nutri Ninja Blender DUO is a special product due to its Auto-iQ Technology. This intelligent program combines unique timed pulsing, blending and pausing patterns that do all the work for you. Auto-iQTechnology features timed, intelligent blending programs that do the work for you, no guesswork required.