Another nice "Bulova 30" dated "M0" and marked 10K GF Bezel/ stainless back. Mounted on a NOS 1960's scissor center GP SS band. This is a front load and I haven't had it apart. The other one in my stable has a 10COAC and I would assume this one is the same. Keeps perfect time. Has a little bit of lume "halo" staining around the dots at number indice markers.
According to the 1960 ad referenced, it's Champagne bubble-proof.