Pack of 3, 4″ Long 40 GRIT Engine Cylinder Hone Replacement Stones40 GRIT Brand: PMD ProductsMost agressive grit hone stone you will ever find for a 3 arm cylinder honeUse with our PMD Products $12.99 Cylinder hone available on eBay (search our store part #97000) or any 3 arm hones that have a 5/8″ Wide Stones ( pictures illustrating the stone holder)Replacement stone holder is 5/8″ wide with bonded stone 1/2″ wideAluminum oxide stones bonded to aluminum stone holderCan use with other engine cylinder hones with 5/8″ stone mountsIncludes three 40 grit hone stonesStone w/ holder dimensions: 4″ L x 5/8″ W x 3/4″ H