K M B. A year ago or late?
In Catholic countries, the Feast of the Epiphany (January 6) is written in holy chalk on the doors of houses and stables by the abbreviation K † M † B † or the Latin equivalent of C † M † B † (or † C † M † B) as a blessing formula. The three crosses symbolize the Holy Trinity, ie the Father, the Son and the Holy Ghost. So they are not "plus" signs between the initials.
- Acer T10