help with naming of a part

Hi everyone,

Can someone help me with naming of a part?

whats the part called where the thermo switch and the other plug sit? mine has decided to leak where it connects to the head, so coolant is going everywhere!

Anone know where i can get it from?

thanks
luke

might just be the rubber o ring that has gone not the flange

try that first before you go a buy another one