Black box under bonnet - part 119.201.801 - what is it?

[RobFrost]

There's a black metal box under the bonnet of my 1970 911T with some hozes coming out, near the nearside batttery. VW Part number 119201801. I assume 119 means Porsche 911 and I know 2 indicates fuel, exhaust and heating. What is this item? I didn't look where the hozes go because I assume I could look up the part number but I've been unable to find it.

[DarthMJH]

It’s a vapor charcoal canister for emissions.

Details taken from another forum:

This system was an early attempt to control emissions from the fuel system. The box under the dash is an expansion tank, while the tank under the fender (with the rounded top) is a vent chamber. Vapors that escape from the gas tank go to the expansion tank (which had to be above the top of the gas tank to avoid the transfer of raw fuel), then on to the vent chamber, which could be lower in the car. After the vapors reach the vent chamber they pass directly to a charcoal cannister (the part that you have to loosen, by removing a rubber strap, so you can access the car's left side battery). Hydrocarbons are trapped by the charcoal, and, when the engine is running, the engine cooling fan purges the charcoal cannister which sends the bad stuff to the car's air filter housing, where the bad stuff is mixed with fresh air and sucked into the engine. The downfall of the system is that the Tygon hoses deteriorate and the expansion chamber cracks, which produces a mysterious gas smell in some cars.

[inaglasshouse]

US cars only.