The B2(10.0)B-XH-A-U: The (10.0)B-XH-A-U: This 2-position header from JST's XH series uses a 10.00 mm pitch, which is wide enough that the board trace routing between pins is straightforward, but the footprint is large for a 2-way connector — plan for the extra board real estate.
Where the 10 mm pitch changes the mating half
The standard XH series header (B2B-XH-A) uses 2.50 mm pitch. This part uses 10.00 mm pitch — that is a completely different footprint, so the mating crimp housing must be the wide-pitch XH variant, not the common 2.50 mm one.