The GroundGrabba Hook Washer is designed to help you anchor down your outdoor equipment where the hole diameter needed to pass your GroundGrabba though is larger than the diameter of the GroundGrabba Hex Head and collar.
The diameter of the GroundGrabba Pro GR13 series have a collar diameter of 25mm. The GroundGrabba Hook Washer HR13 is wound onto the shaft then slid up under the collar giving your GroundGrabba a collar diameter of 55mm (2 1/8")
