I mean a bob cut to the same length!
A “one-lenght bob” is a one-length bob. One-length refers to hair that is trimmed to the same length throughout.
Nowadays, the term “one-length bob” seems to be particularly associated with the image of a haircut in which the bangs are the same length as the sides.
Such a one-length haircut and a bob go together perfectly! It makes a wonderful, cute and mature hairstyle.
One-lane bob is popular among celebrities
The one-lane bob is quite popular among celebrities.
Various celebrities, including Kiko Mizuhara, synonymous with one-lane bob hair, have one-lane bobs.
Many of them are mature, cool, sexy, and beautiful.