The slim 500 ml is about the width of a soda can. Fits all cup holders and fits all backpacks. A great everyday bottle. Our one-touch water bottles are non-toxic, BPA-free, with a fast flow for rapid hydration and a hygienic flip top cover for one-handed use on the go! No annoying screw top or dirty nozzle! 100% leak-proof, 100% of the time.