Originally posted by reeftool Honeywell was the official importer of Pentax camreas and lenses way back in the day so all of the official USA imports were labeled Honeywell Pentax. Lenses and cameras in the rest of the world were labeled Asahi Pentax. The products are identical.
Unless, of course, they are labeled Heiland (a Honeywell subsidiary). In addition to the Honeywell name, there are also some differences in model names for the various M42 film bodies. I don't believe that there were any lenses labeled as either Honeywell or Heiland.
It might also be useful to know that Honeywell sold many different photography products that had nothing to do with Pentax (e.g. Strobonar flashes and Nikor darkroom products).
Steve