Need plumber help

My kids bathtub drain is mega clogged.  I was going to snake the drain and I pulled off the overflow cover (the type without faceplate screws) and got to this thing.  Not sure how I get it out to insert the snake.  Does it screw out or just pull free?  If I grab the stem with a wrench it doesn’t seem to want to turn counter clockwise.  Any help is appreciated 

Link to pic 

http://cubeupload.com/im/Joejitsumd/3853E7C5CF38483E8393.jpeg

 

Not a plumber, but you probably don't want to try to take it apart, it might have something like this in it.

 

Do you have access to the drain from underneath (basement etc)?  Mine has a trap you can remove.

Idk but you could fill the tub with some water and plunge it like a toilet 

64FordF100 -

 

Not a plumber, but you probably don't want to try to take it apart, it might have something like this in it.

 

Do you have access to the drain from underneath (basement etc)?  Mine has a trap you can remove.

Mine is accessible from the other side of the wall. There's a panel they blended into the wall to hide, and if you remove it you can access the shower/bath plumbing 

You need the mighty plunger 

kuttdawg - 

You need the mighty plunger 

By that, he means stick your dick in it.

Try liquid plumber foaming pipe cleaner first before you take anything apart.

VFR -

Try liquid plumber foaming pipe cleaner first before you take anything apart.

This..... works a treat and less likely to have issues afterwards...

Got it figured out.  That stem doesn’t come out.  I removed the brass cover and was able to fit the snake in and cleared everything.  What a pain in the ass.