Inner section to piston

[Cleggy]

I have stripped bakes down to change the seals and give them a good clean.

However the pistions seem to have an inner section with soft matrial on to that would make contact with the brake pads.

This soft material is braking off.

Can this inner section be removed and is it realy needed ?

p.s. how do you remove it

[extonyg]

i also noticed this when i stripped my pistons, i have been told a few things about them......was told they were to help with the heat from the pads not getting to the piston and fluid.......also told to do with 'pad rattle' to help illuminate noise .....both are possible answers.
all i did to mine is sand it down so it was flat and level as mine was all uneven.i wouldnt want to remove it totally.