More Heating system help?

[tonto]

Seeing that there are a number of very knowledgable members on here, can anyone tell me what this is and where i might get another one?

It is my oil heating system, and is in the oil supply line, with a return from the boiler.

As you might see it has a crack in the plastic dome, and is very slowly leaking, not much at the moment, but I do want to replace it sooner rather than later.

I am sure I can do it myself, just need a new part, which is the same as the existing part.

Regards,
Gary

[camelgas]

Its what is commonly known as a tigerloop, the connections are different on the new ones so pipework mods are needed, all joints must be very good or you will get intermitent lockouts. HPS in bridgewater should be able to supply what you need.