Mostly to make the syntax for radius and box similar:
`radius=("1m","3m")` searches on a disk of inner radius `"1m"` and outer radius `"3m"`
`box=("1m","3m")` searches on a box of width `"1m"` and height `"3m"`

The alternative would have been to use `radius=` and `inner_radius=` on one side, `width=` and `height=` on the other side.