Oggy Knobs Removal for Chain Adjustment

[R1der]

Please help.  I need to adjust the chain.  When I tried to remove the Oggy Sliders the previous owner had on, I encountered this as per the attached photo.  There seems to be a washer and they have covered the nut with some sort of glue.
I am at a loss as to how to proceed.
Has anyone encountered this before?
My chain has roughly 40mm play, so it needs to be adjusted soon.
Any help appreciated.
The other photo is from the right hand side.   
What a mess.

[mADmAN]

Wrong thread...sorry

[BartZ]

From what I can see one end is a welded washer with a small notch going in to the plastic slider, the other is just a standard nut. Hold with your hand the slider with the welded washer and unscrew the nut with a socket on the other side. It looks a bit rusty but it should come off.

[zed9]

I wouldn't take a chance with rounding off that nut or else its grinder time. Put some penetrating oil on those threads then use a quality SIX point socket.
Should come off no problem.