The Glashuette Original Alfred Helwig Tourbillon 1920 reference 1-54-01-01-01-01 is a limited edition of 25 pieces introduced in 2020 to commemorate the 100th anniversary of the invention of the flying tourbillon. This watch has a Rose Gold case of 40.00mm, which houses a hand-wound movement with tourbillon escapement. The latter can be viewed though the see-through case back.