Did Promaster quit "making" lenses
Promaster never made any of their own lenses (as far as I could determine).
What they did do, was rebadge 3rd party lenses (usually Tokina or Tamron) as "Promaster". The big diffrence was that Promaster offered a lifetime lens warranty :
"Photographic Research Organization Inc. (PROMASTER) warrants that your PROMASTER Spectrum 7 Lens, purchased AFTER 1/1/2000, will be free from defects in materials and workmanship for as long as the product is owned by the original purchaser."
Promaster offered a lifetime lens warranty well maybe but that was shorter than normal lens makers warranty since nobody was willing to hold on to any of that cra#$polla for any longer than few months.Besides rebaging other makers lenses thay acctualy have them made to thiers specs and some get accounters slash APO ED SLD optics and soem parts been made even chiper than original 3 party lenses.