I keep a spare tube in my pannier on my commuting bike, so that I don't have to do a repair at the roadside and save a bit of time. Once though, I found that a hole had worn through it on an edge of the tube where it was folded. I picked up a tip to wrap the inner tube in cling film, to prevent this happening, which I did. However, on Friday, I had a puncture and found that both the cling film and inner tube had worn through! Any suggestions for something I can use instead of cling film?