·Easy installed and removed: no heating,cooling or knocking while installation; Releasing and pushing  out screws without striking
·Random axial position and radial direction for installation
·Easy opearation in narrow space
·Easy opearation with giant machine parts
·Free from angular and axial backlash
·Overload protection in some occasions (prevent overload slipping)
·Key slot can be added to prevent overload slipping
·Shaft and hub can be designed smaller,lighter, cost and space saveing
·Saving cost by reducing machining accuracy of shaft and hole