A Schild – AS Calibre 1886 – Part No. 301 Regulator for flat hairspring (NOS) Related posts: A Schild – AS Calibre 1704 – Part No. 301 Regulator for flat hairspring (NOS) A Schild – AS Calibre 1711 – Part No. 301 Regulator for flat hairspring (NOS) A Schild – AS Calibre 1713 – Part No. 301 Regulator for flat hairspring (NOS)