Hi Lars , this looks axactly the same as the 'Antares" 90 degree finder I sold with my 90mmLP APO reciently , and if so I agree I used mine a lot as a stand alone scope , awsome optics and build
especially the helical focuser , cool little scopes , you tried to capture the awsome coatings on the lenses didn't you ?
they are invisable .
That good they are , and good luck mate .
Brian.