Our overflow tank PBO 0700 is made in polished stainless steel with a knurled filler knob. There are four sizes available, 13”, 15”, 17” and 19”. A pair of tubes at the base adds a further 2.5” (65mm) and provides connections for the hose from the radiator and were necessary, an overflow tube. Check your connections, the long tube outside the tank are the outlet and the short tube connects to the radiator. Always use the longest tank that you can fit in the available space. Too small a tank my not be able to contain all the coolant if your engine displaces a lot were as a larger tank…