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The Jetco system comes up now and again. It was installed on a few different Winnebago models, with chassis from at least Ford and Chevy.
I believe the part number you have, W015179259, is just a Firestone part number, and it's usually written W01-517-9259. If you google it, you'll find some other Firestone airbags, even some links to threads above talking about the Jetco system.