This C-shaped "washer" fits into the slot at the top of the furler's upper bearing holder and is then secured to the upper end of the top extrusion.
The "washer" prevents the bearing holder and bearing from sliding downward into the extrusion.
This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm.
www.P65Warnings.ca.gov