A coupling on a Waring blender is also called a drive coupling. During blending, the coupling spins, aiding the spinning of the blender's blades. The coupling itself is attached to the base of the unit. Because of the coupling's fast spinning, it may wear down and not work properly after many uses. If this occurs, you can replace the old coupling with a new one. First you must remove the old coupling. Some couplings are hard rubber while others are metal -- it depends on the Waring blender model -- but the removal method is similar.
Turn off and unplug the blender.
Put on leather work gloves to protect your hands from sharp blender blades. Remove the collar around the base of the blender container by turning it counterclockwise. Set the blender container and the blade assembly, aside.
Open up your adjustable wrench and place the jaws around the coupling. Tighten the wrench until the coupling is firmly in its grip. Note that some models have screws in the base that may interfere, requiring you to unscrew those first.
Turn the wrench clockwise to loosen the coupling. After you have loosened it, you may need to work a flathead screwdriver tip beneath the coupling to lift it all the way off of the base.