Can't find this type of single shower handle valve...do you know?

[jackieonly43]

There's no brand or model... I don't know what to do now that I have removed the handle. I turned off water and pulled on the part in the picture...and nothing! Help!

 

[Twowaxhack]

Might be a moen with after market trim.

Take the chrome plates off. Then take and post pic.