Manufacturer
The L. S. Starrett CompanyDate made
1910Notes
6 inch Experimental w/slotted blade. XP but tagged wrong as Cat. #60. See page 82 in Catalog 20 (1913) was first in Catalog 19 (only 2 catalogs it was in) is a New Double Sqare 13S (S for Slotted). Tagged Xp so i would date prior to 1910