Twist pop up bath waste removal

[treefiddyy]

Hi there, apologies if wrong forum section.

we’re trying to refurb the bath drain as the chrome plating has come off. However, there appears to be a ring with 2 slots either side locking it in place. Is there a name for this part and a tool that can remove it? Or, is there another way to change this drain?
It is attached to a twist pop up mechanism if that helps. I’ve attached an image, hope that’s allowed and apologies for the grime.
Thanks

06-A17-F84-59-AC-48-BF-ABDD-EA9-E85-B2-EC1-D hosted at ImgBB

Image 06-A17-F84-59-AC-48-BF-ABDD-EA9-E85-B2-EC1-D hosted in ImgBB

ibb.co

 

[ShaunCorbs]

wide chisel normally works for me be careful the waste doesnt drop too far

 

[Aquarius]

Or a large slotted screwdriver used on one side.

 

[moonlight]

A 2p piece held with a pair of grips. Always get the awkward ones open.

 

[Stigster]

I always used the hook end of an aluminium radiator bracket to work on these. As the other guys are saying, you just improvise a tool to undo the center screw and the waste will drop away from underneath the bath.