Hi all, needing a little help. I have an old Casio AQ-321G, but have no idea what battery it takes. I've looked around online, but cannot see anything... I see a 309 stamped on the case back, could this be it....? Can you please help, below are some pictures:

The radial teeth are for hte seconds register, and the other (which is simple and doesn' take away significant torque from the train) for the minutes register.

The original 6139A manual is very clear in how to disassemble and how to assemble ...... step-by-step. However I haven't seen the 3169B manual, even in the Japanese version around, which clearly highlights the difference in center-wheel.   6139A Seiko Technical Guide.pdf 6139_A.pdf 6139A.pdf 6139b.pdf 6139B repair guide jp.pdf        

Hi as an addition a pertaining to the assembly of a 6319B  which will be handy for those working on this caliber Polly's 6139 guide.pdf 6139A.pdf 6139B.pdf

Casio MDV106G-1AV Gold DURO200 I'm going on a long family vacation to Southeast Asia this summer and wanted a cheap but reliable beater in case I lose it, break it, or get robbed. Quartz movements aren't my thing, but I'm not dogmatic and this was a cheap option. A few years ago you could buy it for under $50, but since this particular model with the Marlin fish has been discontinued, you have to pay about double that, but I still thought it was acceptable. Sure, I could wear one of my cheap and very reliable Vostok Amphibian divers watches, but I have a personal relationship with them (having put a lot of work into them) and don't want to risk losing them. Strangely, I feel very excited. Maybe because I haven't bought a brand-new watch in over 10 years! 😀 The only downside is that this is the watch Bill Gates has been seen wearing, and I'm not exactly a fanboy of Bill Gates. Anyway, who cares!?