We will request you in a survey to exactly measure your feet manually in a pre-defined way, to be sure to choose the best size. FYF is very flexible over multiple sizes, but of course we want to deliver everyone the ideal size. That's how the measuring tutorial will look like: http://FYF.io/pages/guidance-for-size-selection
Cold hand wash or a very short, cold machine wash is fine too. If odor occurs over time when washing only cold, bath them in alcohol based sanitiser, that will clean FYF from the bacteria that cause odor.
It will absolutely be possible to get them in different size. For each pair of FYFs you backed, you can choose between all 10 options that will be available: FYF swiss-classic & FYF low-cut www.FYF.io/pages/fyf-styles in all 5 sizes. We will send out a survey, even requesting you to measure you feet then following this tutorial: www.FYF.io/pages/guidance-for-size-selection We will add a video tutorial on measuring your feet' size as well. Generally, no need to worry - they actually stretch over several shoe sizes - so it will be really hard to get the wrong size.
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