Pack of 3, 4" Long 180 GRIT Engine Cylinder Hone Replacement Stones 180 GRIT Use with our PMD Products or 3 arm hones that have a 5/8" Wide Stones Replacement stone holder is 5/8" wide with bonded stone 1/2" wide Aluminum oxide stones bonded to aluminum stone holder Can use with other engine cylinder hones with 5/8" stone mounts Includes three stones Stone w/ holder dimensions: 4" L x 5/8" W x 3/4" H