That really is what it's called in the owners manual (see pic). It is however, a rubber strap with a VW Part Number; 171-011-247.
This glorified rubber band was used for a few different applications by VW. The most common application was to secure the jack to the steel wheel of the spare tire. This configuration was used on most MK-1 models of the 70's and 80's, Rabbit, Scirocco, etc.
Congrats to William in IN, Chris in PA, and Mills in NC, who were the quickest folks to guess this part correctly, with the VW part number.
Hope you had a little fun with this one; thanks to all who participated!
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