UPC was a company that was around in the '60s. They sold reboxed versions of other companies kits.
In this particular case, the UPC MB-2 according to Scalemates is a rebox of an "original" kit sold by Marusan.
Marusan inturn was known for both selling repops of other companies original molds. But also for pirating other models. I can't find where this one falls. The original ITC kit came out in 1959, the Marusan kit in the early sixties. My own guess would be that Marusan pirated the ITC model.
The kit in the OP was an ITC mold, reboxed by Kleeware, reboxed by Ringo (ITC brand), then by Glencoe.
The contents of that UPC box may be an adventure.