John, I have Art Burton's give away from several seasons ago. I think I increased the tube size on my own, but I haven't experienced any deterioration in the time I've had it, now two, maybe three seasons. My experience with truck tire tubes is thus: If they have no visible deterioration and don't deflate from full within three to five days, then you're golden. It takes a hell of a lot; sun, heat, abuse, ignorance to get one to the point of disuse. I have several I use at the lake each year for goofin, and they sit in the barn loft winter after winter, and keep coming back to life each year. In fact, I didn't deflate the float tube last year at all, and it's still fully inflated as I write this.
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