Help ID Mexican Maker's Mark-Sterling? Bracelet

I've tried to search online for this Made in Mexico Silver bracelet maker, but haven't found a match. Does anyone recognize it? Also, is it safe to say it's sterling? I tested with a magnet which doesn't react at all, so it's not plated. I don't know of any other way to test. Ideas?

 

That's an old style mark, generally used before 1948. I'd test it to make sure of metal content, because some "beach jewelry" was marked silver but wasn't. No idea whose mark that's supposed to be.

 

Acid testing could ID the metal, if you're not familiar with that have someone who is assist. Or, ask a jeweler to test for you. Some use acid, some us XRF machines. I can't hazard a guess at maker, I imagine it might be 2 letters?