intermittent drips, but need help identifying

[proo]

I have a shower that drips from the top wall-mounted head occasionally. I'd like to fix it before it becomes more urgent, but I can't find any identifying logos or names etched on it.

It has a separate temperature control; the top handle controls the wall mounted head and the bottom one controls the one with the hose. I haven't worked with one like this before so I'm not even sure which handle to remove and how to go about it. Since it's still perfectly functional, I'd rather get the parts first before risking opening it up and making it worse, but if I have to I will.

Any help or advice?

Thanks!

 

[proo]

I'm reluctant to start ripping into it until I know what to expect, as it's the only working shower in my house right now. I've only had experience changing the cartridge from a single-handle shower before, so I don't know what parts I would need for a shower like this. Do they have "cartridges" as well? Is the problem likely to be in the top flow control handle, since that's the head the leak is from?

I don't see any exposed screws; what tools will I need to finish the job? Should I start prying the ends looking for a snap-off cap (it's not obvious) or just grab a wrench and start twisting?

Thanks for any tips!