Department of Army supply catalog. Ord 8 SNL. Field and depot maintenance allowances. J-494. Grinder, pneumatic, portable (pistol grip handle), (1) size 6 x 1 in. wheel (vitrified), and (1), size 8 x 1 in. wheel (organic) (Chicago Pneumatic Tool Co. no. 331-P-4250) (40-G-169); Jan. 1950.