That's not the hacksaw that appears in the 1942 catalog.
Same model number, but different adjusting mechanism.
What you have there is the new and improved version of ye olde No. 99, patented by Harry Kulp in 1950. The patent number (2,531,135) should be stamped with the branding on the dynamic piece, either on the side you're showing or the flip side. Mine is, anyway. If there's no patent number, it's likely fairly modern and they didn't bother displaying the patent number after it expired. I have never seen one with such a shiny finish, which might also be indicative of later production. I posted photos of mine along with a catalog excerpt and the patent diagram in a post upthread linked
here.
Their first No. 99 was patented (1,382,448) in 1921 by G.H. Wilkins of Greenfield, Mass. As I said in the K-D thread, I have not been able to determine if they licensed it or bought him out, but they used his design through 1947. It appears in the 1934 and the 1942 catalogs, but is replaced by the new design in the 1948 catalog. Kulp applied for the patent in 1946, so they were making it before it was granted. You can read more about the first hacksaw and see patent diagrams in the K-D thread, post #3.
@tombell572 has one of the early models as well. His is posted upthread here. See #126.
Here are both K-D frames, early and later.