Aftermarket reproduction Coolant Distribution Junction
Now... pay attention... this might get complicated.
This is a coolant distribution junction for T3 Petrol models fitted with the "Late" cooling system which was fitted from around 1985.
However... whilst its the "Late" cooling system, its the later version of it.
So, its an Late - Late - Coolant distribution junction.
Got that? Good.
Basically if you have an 1986 on petrol engined 2WD T3 with a Manual gearbox built from chassis number H_022957... you'll have this distribution junction.
Or... the easy way to tell is that this one has no "spout" in the middle of the upright, the "earlier" one has one... there is also an Automatic version that has 2!
The really easy way to tell is look at the part number on your old one!