Looking at this 1964 Tri-Compax

and this later execution

we often read case design is close to the Speedmaster

my opinion is they are based on the 1st execution Polerouters cases designed by Gerald Genta

The Tri-Compax has two great ambassadors

Harry Truman

and Jean Cocteau, the French poet, who wrote many things about UG

Nicknamed "Poorman's Patek Philippe",
their in-house calibers are considered as some of the very best (although they don't show fancy parts finish),

UG is a difficult brand to collect,
some parts of the brand story is unclear,
very few good/original samples available on the market (owners simply don't sell I think),
parts (at least hands, dials, cases, pushers, ....) are almost impossible to find,
no organized community (although many enthusiasts)

it maybe adds to the experience in any case the UG watches are a joy to own and wear