Suits: Nissan Patrol GQ TD42
This is the heater hose that connects the heater to the engine, this is one of the two longer hoses.
The brand of hose is GATES who make quality aftermarket hoses.
Over time, hoses become hard and this makes them weaker and prone to cracking, causing you vehicle to loose water and overheat. Generally if one hose goes, it is possible for others to go soon after, so sometimes a good idea to replace your other heater hoses at the same time.