Natural Stones In Ideal Gunsmithing Shapes
Carbon steels just seem to polish best with a genuine Arkansas
stone and the four shapes in the kit have proven to be the most
useful in the gun shop. The edges are nice and clean, making them
an excellent choice for flat trigger and sear faces plus most other
gunshop fitting chores. Fine cut, white hard Arkansas.
Big Book Catalog, Issue:65, Page:458
SPECS: Set includes - 1/4" (6.3mm) x 4" (10.1cm) Triangle; 1/4"
x 4" Square; 1/4" diameter Round; 1" (2.5cm) x 4" Knife tapers
from 1/4" thick to 1/16" (1.6mm) thick.