This is a A-B1RBG981 ROTARY BLADE GRINDING STONE 981 PN: B1RBG981Main Description As Following : A-B1RBG981 ROTARY BLADE GRINDING STONE 981 P.N: B1RBG981 Use with B1RBG934 Rotary Blade Grinder.Center Hole: 5/8"Diameter: 9"Width: 1/4" Found in Section & Models : Sunbelt - Blades > Blade Tools & Accessories, (Miscellaneous) GRINDER, BLADE: SEVERAL, Sunbelt - Equipment > Grinders, (Miscellaneous) GRINDER, BLADE: SEVERAL Associated Items : A-B1RBG934 Also This is An Aftermarket Product And : Use with B1RBG934 Rotary Blade Grinder. Center Hole: 5/8" Diameter: 9" Width: 1/4"