Is that like a protective material that is harder to puncture than the rubber of the tube if something gets through the tire?
What if you put in your new tube, then put slime between the tube and the tire before airing it up? LOL Ultra flat protection?
I bought a kit once had a bag under my seat with a small crescent wrench, spare tire, automatic air-up co2 cartridge device I bought so I could do flat repairs on the trail