Protects Surface of Glass Against Scratching or Chipping Replacement Washer for 3/4" (19 mm) Square Standoff Cap Assemblies This CRL Clear Vinyl Washer is designed to work with the 3/4" (19 mm) Square Standoff Cap Assembly to protect the glass edges around the drilled hole against chipping and scratching. NOTE: This washer is included with the purchase of the Cap Assembly which includes the following items: One washer with small hole, one washer with small hole and attached sleeve.