The Radium tank has a 1.5 bar cap, this is higher than the stock 1.3 bar cap. This raises the boiling point of the coolant and reduces the likelihood of the water pump cavitating at high RPM.
We started by removing the stock coolant tank. The tank is pressurized so be sure the engine is cold before attempting to remove it.
You can see how the stock tank is shallower but big from the top view and the Radium tank is smaller from the top but is much deeper to get its volume capacity. Overall the stock tank still has a little more capacity. The deeper radium tank might be more efficient at bleeding air out though.
Since you can’t see through it’s billet construction, the Radium tank has a sight tube on the side to show the coolant level in it.
Once assembled, the Radium tank bolts right in, in place of the stock tank.
The Radium coolant tank fittings adapt the stock rubber lines to the tanks AN fittings. Conversely if your engine is plumbed with AN hardware it will attach directly to the Radium tank.