I should actually read more and skim less.....
Upon closer inspection of the catalog, a "BP" marking refers to a uni-directional device and an "XP" marking would refer to a bi-directional device.
What reason did you have to ID this device and what piece of equipment is it installed in, along with any fault symptoms?
I think I have probably gone as far as I can on this, but answers to these questions may help other member to solve your issue.
Kind regards,
Mick.