The Era 2 supports radiators up to 280 mm in the top of the case, but there are a few restrictions one should be aware of.
The maximum radiator length in the case is 315 mm, but any radiator above 300 mm in length will have a maximum thickness of 52 mm, including fans.
Any radiator shorter than 300 mm has a maximum thickness, including fans, of 58 mm.
It is possible to have thicker radiators than 58 mm, but requires radiators shorter than 250 mm, adjusted to sit as far towards the front of the case as possible. If that is done, the maximum radiator thickness would be 68 mm.