MK4 Golf component identification?

[CPWilliams]

Hi all, located between slave and master cylinders, leaking.

[CPWilliams]

Obvs this is rotated 90 degrees, oops!

[GreenV8S]

I don't recognise that component, but if it's inline in the circuit to the rear brakes then it's probably a bias valve.

[chammyman]

Hydraulic clutch damper. If you removed it you can dump the clutch properly.

If you search bmw clutch delay valve it will shed more light on it (they always remove them)