5 lbs. of hard-working stainless steel tumbling media that easily cleans the most heavily tarnished cases, both inside and out - including the primer pockets - without harming the brass. Stainless steel media never wears out and never needs renewing like treated organic media. For wet tumbling use, do not dry tumble. Not for use in vibratory tumblers.
Brownells Christmas , Issue:3X, Page:013
Big Book Catalog, Issue:66, Page:519
Sinclair, Issue:3B, Page:080