Model 299 & 300

54 Grit Stem Grinder Stone. 

4" Diameter,  Straight Cup style, 1" overall thickness with 5/8" Hole Diameter 

Fits All Sioux / Thor Model Valve Grinders Except 682 and 685L, KO Lee Model K500 and K403C
OEM Part Numbers: 75571VR2M89, 73533, RV4GQKMB

60 Grit General Purpose Valve Grinder Stone. 

5" Diameter,  Offset style, 1" overall thickness with 5/8" Hole Diameter with 20 degree face angle

Fits Black & Decker Model P, PC, PCB, T, TO, TC, TD, TG, 282/550, 6300, 6305 Valve Grinders

OEM Part Number: 34131