How do you remove a back off a old sei...

Some Seiko watches have threaded back that screw on and others just snap off, the threaded ones are a pain without the proper too;s to remove it. The smart thing to do is to take it to a wal-mart and tell them you need a battery or either you need it cleaned, let them worry with it and the good thing is if they break it they buy it.

If you see the indentations on the case back to accomodate a tool, then you need that tool and unscrew counter clockwise. If you don't see those indentations then the case back then you should be able to pry by using the proper tool. You might be able to use a small bladed tool, like a knife, but be very careful that you dont slip and cut yourself. Go between the case and one of the band posts to get leverage.