Glashütte Original launched the Senator Perpetual Calendar Boutique Edition in 2015, exclusively available at their boutiques. This version of the Senator Perpetual Calendar comes in a sleek stainless steel case and a stunning blue dial with Roman numerals, all crafted in-house at GO's dial facility in Pforzheim. You can choose from three references, all equipped with an alligator strap. Reference 100-02-07-12-01 has a classic pin buckle, while reference 100-02-07-12-30 and 100-02-07-12-50 offer a folding clasp, with the latter having a shorter one.