Radiator Overflow Tank

Hi

I'm new to Jimny's having only bought mine 3 weeks ago. One thing I've noticed under the bonnet is a plastic tank, similar to a washer bottle, and to the right of the radiator, connected to the radiator by a black pipe. From the tank there is a second pipe, arrowed as out, that ends after about 50 mm. I can't see anything that it was ever likely to have been connected to.

Does anyone know if this is just an overflow/header tank for the radiator or is there something I should be worried about?

Its to stop the header tank pressurising when the hot water come out of the rad

Thats the expansion bottle, the pipe you are seeing is the overflow for the bottle and is supposed to be connected to nothing so that it can spill over on to the ground if it needs to, unless you overfill it or there is a problem with the cooling system then it will likely never overflow out of that pipe.

Excellent. That was my best guess for what it was but I wasn't quite certain.