They are stamped (6″ REVERSIBLE JAW) on the top. Type: Vise Jaws. Sub-type: Vise Jaws Bracket Kit. 2x Vise Jaws. This is likely consistent with the original design. Material：High quality aluminum. For Many Craftsman & Columbian.
Aluminum Machinable Soft Jaws for 6″ Kurt style Vises. Jaws are machined on all sides. square and smooth.