A nut for a given thread size is defined by its shape, width and thickness. The shape is either "hex" for hexagonal nuts or "square" for square nuts. For hexagonal Imperial nuts, you can choose from ...

bevel if true, bevel the outside of the nut. Default: true for hex nuts, false for square nuts bevel1 if true, bevel the outside of the nut bottom. bevel2 if true, bevel the outside of the nut top.