kyBoot shoes are generally wide, up to 4E (EEEE). We have several different sole types/shapes that fit a variety of widths.
There are also volume adjusters (filler insoles) that assist in making the kyBoot fit a little more snug if necessary.
Ultimately, it's the combination of the sole and upper material that defines how wide the shoe feels. For instance, mesh upper will feel wider than leather, even if it is on the same type of sole. This is mainly due to the flexibility of the materials.