This tube is often missing and it's very important for 2 reasons. First, it keeps dirt and junk out of the throttle tube, which then abrades the cable. Also water (rust). Secondly, it keeps a constant tension (throttle setting) while the engine moves around a bit. If this is missing, you'll find it very difficult to control the throttle, every wiggle the throttle changes! The result is a bucking monster.
610mm in length
Suitable for 1966-71 and 1978-79 Beetle
Volkswagen Part Number 131721551