For Fine, Precision Marking
Automatic, one hand operation leaves the other hand free to steady the work. Fully adjustable for strength of impact. All working parts are hardened.
Big Book Catalog, Issue:66, Page:452
SPECS: Steel. 3-53/64" (9.7cm) long. .405" (10.3mm) diameter. 1½" oz. (42.5g). Knurled body and adjusting cap. Starrett #18AA.