This unit is used to to attach the STEM SYSTEM to the chair. The MCxxx portion is used to attach to various sizes of round, square or rectangular tubing and the UACxxx portion attaches to the Connecting Stems (SCS-xx) with the aid of a 7/8" Delrin sleeve or attaches to a 7/8"Stainless Steel tube. The chair mount and Connecting Stem are held in place by the tightening of two bolts on each clamp.

The exception to this set-up is when space around the wheelchair is limited (such as a backrest) therefore making it difficult to use a ACxxxxIP. In this situation you would use the UACxxx to attach to the chair (round tubing only) and use the ACxxxxIP for attaching to the Connecting Stem or Stainless Steel tubing.