A wealth of information can be found here (in Italian): [url=https://www.dark-star.it/astronomia-articoli-e-test/test-strumentali/vixen-custom-80m/]Dark-Star: vixen-custom-80m[/url] These Japanese scopes began to be produced in the 1970s and continued into the 1980s. Todays Vixen A80M is an evolution of these scopes.